It'd be nice to have a small overhaul of a lot of the windows. I've already seen a few on here that look great.
I'd like to see a collapsible window for the Homunculus window, as it has too much information and takes up a lot of space - I tend to leave mine open to check on when it needs feeding etc.
Something similar to that so you can minimize it to just see more essential information. - I also added an intimacy counter over the traditional Cordial / Loyal etc. as well that sucks.
Also unless they are going to be used are the Accessory (Unequipped) (I'd really like to see this as a possibility for Homunculus S, and them having alternate forms), really necessary they just look horrible (if they are going to be used it's own single or expandable set of equipment box's would be nice to see, just makes it look tidier.
One last thing would be to stop the window disappearing as you go through portals, some maps have loads, or if you teleport it closes, just a bit annoying if you have to reopen it all the time.
Anyway just an idea. Just like Alt+V does but I guess just with the little minimize button.