Okay, I'm near the end of my first full game on Diversica, and have some end game feedback. This is the second one I've played; the first was with Revolutions enabled, and I had to start over because of errors. The second one (without Revolutions) was an absolute blast. Thank you; that was the most fun I've had playing Civ for awhile.
A few units seem to have their Civ-specific color not showing. Ones I noticed were War Elephants (can't recall which one, but it may have been either Khmer or Babylon) and Babylon's Paratrooper. You know the bright bluish (or is it violet? I'm not sure because I'm colorblind) tone that is supposed to get replaced with the Civ color? At least that's the way it was in Civ3, so I'm assuming it still is that way. Instead of the proper civ color, that bright blue/violet color was showing.
The graphics for Arcology, Arcology Shielding, and Deflector Shielding are too big and obtrusive. They are made to appear concentrically, with each dome inside the prerequisite before it. When you build all three, it is almost impossible to see what is on the land tiles immediately surrounding your cities. Would it be possible to have these graphics replace the ones that come before them, rather than all appearing together inside one another? It would be simple enough to tell which one the city was upgraded to: Arcology is plain, Arcology shielding has one rotating energy field, and Deflector Shielding has 3 rotating lines in the energy field. If these just appeared as an overlay directly on top of one another, it might work.
I noticed some oddities with the Mech units. First, it appears that the Ultra Mech doesn't have a limited number of national units of it that can be built. Assault Mech maxes at 4, Behemoth Tank maxes at 2, and then it appears Ultra Mech is unlimited in the number you can have at one time. Is that intentional?
I was also surprised that out of the three Mech units, only Behemoth Tank had a required resource (Iron). It would be really nice to have Iron required for all 3, or Aluminum and Iron, since these are really large and tough units and it would make sense that you'd have to have a large amount of raw materials to build them. Too bad we don't have Titanium as a resource in the game; that would make a great required resource for the Mechs and the future aircraft.
I noticed that the Destroyer upgrades (Stealth Destroyer and Sensor Destroyer) all had the same strength as the normal Destroyer. I wasn't sure if that was intentional.
The strength of the Guided Missile is 40, but the strength of the Biological Warfare Missile is 14, even though it is higher up on the tech tree. Even with the +100% strength vs. certain types of units, this still seems oddly weak.
Lastly, I noticed that when one of my vassals researched the Astrogation technology, the tech was not available on their list for them to trade it to me. They had been able to trade all their earlier techs with me, so this seemed odd. I have technology brokering disabled, but I'm sure he researched it himself because I watched him finish it (via passive research spying) and no one else has researched it, so he couldn't have gotten it from anyone else. I wonder if it's an oddity about this particular tech.