Perhaps I'm necro-posting here, but I've always preferred cleaner in-game UIs without numbers everywhere. I'm a vibe player and don't drill down on numbers too much, especially when the game is real-time and fast-paced like 0 A.D. is. In single player, one can read read read to one's heart's content, but in the heat of battle I really don't want numbers bogging me down--only the performance and abilities of my troops matters. What they are good at. Who they counter. What they don't counter. What counters them. In the Unit Viewer we can pack as much information as possible, but in-game, I'd personally prefer minimal, which is what the current layout, more or less, provides. I have my own quibbles with the current UI layout, but those are mostly with the popups -- the unit viewer, the tooltips, the diplomacy screen, etc, which can all be vastly improved.
Here I've been (for the 70th time) working through some tooltip layouts:
We could definitely post more threads on the various UI topics and I'm more than willing to mock things up. It would be nice @Atrik if with your skills you'd be willing to mock up some working examples from what we discuss. It's something I think we could start to transition to Gitea with @Vantha and others. I think it's high time we actually, truly improve the UI in these areas. Add some real polish if we're ever to put this game out to the wider world on a platform like Steam.