I think the 'generic' theme could be based on this Athenian example. Just remove all of the Athenian-specific things, like the owls, anchors, and ocean waves. That way, when a modder adds a new civ or the base game adds a new civ, the new layout will still work without necessitating a whole new theme right away. The theme for the new civ can be created later and will be helped with the fact that there will be a dozen examples of how it's done.    I really like how the bonuses are represented by stencils, while the 'entities' such as technologies and buildings are represented by simplified, aesthetically pleasing round icons. 

Yes, I liked several of your suggestions. They seemed sensible and, more importantly, straightforward to implement and likely to get accepted. Unfortunately, I just haven't had the time to work on them yet.   I also agree that this redundancy should be removed.     This one is very clean. Love it!

It’s being implemented in Classical Warfare AEA! We don’t quite have the attack part yet, but at least you can receive bonuses while in formation for moment. In particular Phlanax and Testudo. I may add/tweak a few more.

I agree that a lot of them are visually noisy. In anything final, I'd reduce a lot of the noise in the textures and not pack in so many flourishes and details. I think the Athenian one is perfect for what I'd aim for. I'm super fond of the Han and Syracusan ones too.  These are only mockups. The techs, bonuses, etc. in most of them aren't real.  The ones which are real I had to do a lot of work to force the LLM to pull the relevant data from the civ profiles in Trac, which are outdated of course. The LLM doesn't have the entire source code and public mod inputted, of course, let alone Delenda Est.       

@CoyoteTango I, and many here, agree, as you can see in my suggestion: This is known and discussed, as is maintaining formations during attacks, I think some have been working on it a bit, but it could be that others are against it, although I fail to see the appeal of preferring fighting blobs of units instead.