With a long torso, it's hard to get the proportions set. Making the ab plate a bit shorter may still help get The Look correct; confirm with your Ruus'alor to be certain, and mock it up in cardboard before chopping into your plates. Aside from possibly tweaking the ab plate, your collar plate seems wide. Shown in the laid out plates, it looks like there's almost an inch/25mm of extra width to either side of the chest plates, and it seems like it's there when you have them on. Checking the CRLs, the top corners of your chest plates and the bottom corners of your collar plate should be about the same width, and if not the same, the collar would be narrower than the chest plates by a little bit. You can try adjusting spacing on your chest pieces, but ultimately you'll probably need to trim the collar plate.
Your shoulder plates might be a little small for you - if they sit comfortably and move with you well it may be fine, but I think a bit larger will be better. How are they attached? They are usually attached to sleeve caps on the vest. You may need to move them higher up to meet the spacing & placement requirements anyway, so even something as simple as some short straps of webbing attached to your vest to hold them on might work. Again, consult your Ruus - don't take the word of Rando Mandos like me as gospel.
All that said: your plates are looking pretty good, and don't seem to be floating; it's a bit hard to tell with your body slightly turned.
Advice for photos - get square shots as well - head on, side, side, back. You may need a friend or relative that owes you a favor to help (I have my older kid do it, they usually like helping the old man with nerd stuff). The 3/4 turn is a useful additional view but it makes it harder to see things like spacing between plates clearly.
As for the belt itself - the dark color of your belt and the shirt behind it makes it difficult to see clearly in your latest picture. Since it looks like it's modern law enforcement/tactical gear, as you indicated earlier you'll want to swarz it up a bit. I personally prefer leather and canvas, but the advantages of modern gear (readily available, lower cost, practically indestructible) are hard to argue with. You'll definitely want to do something to dress up the buckle - bare plastic side buckles just don't look right, so drybrush some silver highlights or make a more swarzy cover or front plate for it (you could replace it with a metal one the same size, paint it and distress the paint). The pouches would probably be good with some weathering and maybe put some little metal plates or other greebles on the flaps to add some flair.
Be careful with black on black on black or other dark over dark layer color schemes - monotone sounds cool and looks neat when you try it out on screen in Mando Creator etc. but in real life the layers can just melt together and it's hard to tell what's going on - you don't have the crisp linework separating your parts in real life. Monochrome with varied shades keeps the dark on dark scheme but makes the layers read better, so if your flight suit was faded just a bit compared to your vest, the issue goes away. Weathering at the edges of layers will further highlight and improve the look.
The pop of purple with your sash is a good move - it cuts the monotony well and makes a clear visual break from upper and lower.
Overall, vod, you're off to a good start and nothing that has been pointed out is unsolvable. Also solid choice with the Westar, its Iconictm.