Here's my current concept:
I call it the Mark P, since it's my personal variant on the movie designs. Photoshopped this together from images from the Marvel Heroes video game. Basically it's a hybrid of the Mark IV (Start of Iron Man 2) and Mark VII (Avengers). Mainly the abs, upper arms and shoulders come from the Mark IV, and the overall paintjob (no silver) with the rest being from Mark VII. Also, since I'll have to use a black undersuit, I went ahead and worked that in to see how it'd look.
I attempted a similar suit, just by eyeballing the Mark IV back in 2011, using EVA foam floor mats. The result was sadly under-par, and never truly finished. I didn't complete a helmet, and most of the pieces wouldn't even stay on me.
But I've had time to rethink how I'd do it, and did a minor test last ComicCon with my Tony Stark costume.
Also, I've been inspired by the youtuber Stealth and his tutorials, which really simplify alot of my problems. He recently finished a full Iron Patriot suit in under a month, which really has me hopeful I could do something similar.
I'll post the progress here as I go.