First thought is "extremely elaborate." I reckon your treatment is going to be much simpler, plainer of decoration. And I guess you're thinking more "costume" than "protective gear for LARPs (for which this is overkill) or SCA Heavy (for which this is about right)" -- the suit on the right, which looks to represent lamellar armor -- several hundred small pieces thonged together -- is very good for SCA Heavy body/kidneys protection.
Artist-illustrator-driven fantastickal armours like these two, I often comment they are fun to look at, but the illustrator has only the scantest idea of what armor really looks like. Or how it does what it does -- case in point is the Warcraft 'toon armour, which isn't ergonomic at all and extremely bulky and clumsy (so, I guess, they can't fit through tight dungeon passages!). I often look at pictured harness section by section; I'll go from top downwards.
1. The gorget, that silver plate piece about the neck/collar line on the left suit: Gorgets without articulation to give them some flex port and starboard to accommodate raising your arms will bind you -- though such articulated types could be found in early 16th century German style harness, teamed with a special, low-cut breastplate. Plate gorgets can be solid to about two inches either side of the neck; any wider and they really ought to flex somehow. The righthand suit doesn't seem to have one.
2. The large spaudlers with lames to the upper arm seem of leather that I hope is hardened. These are going to mean some pretty large pieces of leather to form over lefthand and righthand wooden block forms to round them by wet forming and then bake hardening in a very slow kitchen oven, temperature about 180 F. Large amounts of leather mean large amounts of money you'll shell out. You might consider if you want these to be plate pieces that you do them in 16ga steel with a soft hammer and a hard anvil, such as a two-foot length of railroad track if you can find a scrapyard with hefty stuff like that. (Real anvils run into money and cheap Harbor Freight anvils are too soft, quite small, and pretty much worthless except as backup for cold chisel cuts or rivet setting. RR tracks are just as good as real, good anvils for armor building by hammering.)
3. The steel plate elbow cops I'd save up and buy. There are professional armoring shops out there both SCA-capable (nice and sturdy to be beat on), and cheapie, thin Indian stuff that frankly you don't know what you'll be getting. Indian shops don't wear nor use what they make. They just know Americans are a market for such products. These cops will need somehow to be held up using thongs, and held in their place by strap and buckle; you need 'em both because gravity. But they are available on the market, and fairly inexpensive really if you shop around. One of those cases of don't spend too much nor too little.
4. The leather vambraces to the forearms I don't think I'd bother with as depicted. They look like engineer boots that somehow got put on the wrong limbs. Noting the presence of scale all over the harness, either make do with the scale or slip hidden reinforcement in the form of splints on the forearm *under* the scale.
5. Gauntlets: there's so much to be said about articulated gauntlets of plate -- they are intricate and carefully fitted and good ones can go a thousand bucks the pair (and are extremely protective against extremely wicked weapons) -- that they can be a whole construction thread all by themselves. The Society for Creative Anachronism has found and succeeded with a number of different hand protection schemes and we are still in possession of functioning hands even after years of battling. The least expensive "protect from broken hands" system was and is a steel basket hilt fitted to the planed and rasped rattan sword, with what they call a half gauntlet, being a hard cuff and hard plate over the back of the hand and base of the thumb. The basket covers the fingers, the half gauntlet everything else up onto the forearm, and these are the easiest parts of a gauntlet to cut out and fit together right, so they're pretty cheap too.
6. The breast and the back: those little rectangular things on the breast of the lefthand suit are only functional as ballast, not armor -- note the wide gaps between each of them. A point goes straight through the gaps -- you want a plate, you put in a plate, not little bits. (Get me started on the "playing card" suits in Braveheart sometime. Mega awful!!) A rigid breastplate's rigid portion stops at the height of the belly button, maybe to a couple inches below. Anything below that should be a series of articulated lames. Or else you can't bend over without bidding fair to neuter yourself. This is really uncomfortable.
I like the lamellar torso armor on the right much better. Lamellar needs two tools to make from steel pallet strapping, which can be bought in bulk online as even better than scrounging it for free out of dumpsters. Lamellar has a bit of flex and takes much less of a shop to assemble well than armor composed of larger plates.
7. The macho snazzy belts are actually useful -- they place some weight on the hips, taking it off your shoulders. So -- as is! They can carry short weapons like daggers. Swords and other lengthy weapons should be worn on their own easy to remove belt so you can bloody sit down in a chair! (This was a pain in the asterisks in olden tymes too.) You can use these belts as projects to increase your leatherworking skills and experience, and make the belts really pretty and well finished looking: not like a 10 year old made them in summer camp leatherworking class. I've seen people trying to sell stuff, commercially, of that 'quality.' I didn't buy -- I knew I could make better.
8. The lames over each hip are okay too. All armoring of the hip joints is roughly like a skirt, more or less, longish or quite short. These too can be hardened leather without a big problem. They will be suspended and articulated using soft leather straps disposed vertically down the back of the lames, letting the lames flex.
9. I sure hope the wearer has a way to take a piss out of that leather codpiece/brayette. Brayettes are pretty much 'nad-armor.
10. That's a dreadful system for thigh armor, on the lefthand suit. Cuisses should be more comprehensive and not of scale if you want them to keep you uninjured. Hardened leather's okay and there are other easy construction ways to protect thighs. See the righthand suit for a better scheme.
11. Knee cops, as for elbows: buy these and save yourself time and fuss. These too will need holding up and holding in; the cuisses are a good suspension for kneecops, the cuisses themselves being held up from a waist belt unless you hang them from the arming-garment/arming-doublet I describe below. Armor is heavy, and needs to be suspended from either the shelving parts of the body or the decidedly narrower bits -- like if you boast a non-podgey waist. If you do have a pudge, then the long-vest sort of garment in the next para would be the best hanger for your legharness.
It is good engineering to design and build a light, strong vestlike (or sleeved) cloth "foundation garment" to tie and buckle the heavy hard bits onto, then fit the heavy and hard to it. The very best fabric for it is 100% linen. Nylon strap reinforcements included are okay, but you need the cool riding of as much discount linen as you can get -- about six yards total, for doubling up -- to keep from sweating half to death. Expect to do some sweating anyway. Comprehensive plate armor is comprehensively hot too. Stuffy.
12. I'd junk those greaves. The hard parts seem to neglect any idea that sharp threats might come from dead ahead! They look cool, even racey, but they don't work any better than the vambraces with the same problem. Other designs do.
I've even run across a cheap and easy way to make good looking hard greaves molded to your own form -- hard greaves that totally enclose the lower leg have to be precisely fitted or they slip and chafe holes in you. (this is fussy to do in metal with hammer and anvil) It's called "laminated canvas armor," and is made about like papier-maché of cut or ripped strips of fabric (muslin will do) dipped in Titebond III glue. You can put the messy strips on yourself while they're still wet, shaping them to your person as you go -- cover yourself with Saran Wrap. I think you should start with just a couple-three layers thick at first so they'll dry quickly while you sit with your leg stretched out watching TV, etc. Make sure you've left a gap down the inside of the leg so you can pry the thing off after it's dried; it has some spring and of course you can size the gap wider or narrower depending. The guy(s) who came up with the stuff for SCA broadsword combat figure it needs up to six layers of glue and fabric/light canvas at about its thickest for SCA-type pounding, something about a quarter inch thick. They can shelter your ankle bones. It is easy to taper the thickness down where wanted -- leave off some layers one at a time. This makes really good looking, perfectly tailored all-enclosing greaves that can be any color or painted leather color or even leather covered. You can rivet metal splints to these too.
I'd still like to hear for sure if your intent is costume or playing rough.