The British troops are the only ones in the game that are different on a mechanical level. Every other troop merely has a difference in DPS/HP or both. In addition, shooters only take one space, are the cheapest to upgrade in the armory and second easiest to max in uni. And they get 15% bonus damage on top of it and the loot bonus as an extra kick in the teeth. Ultimately, the range itself is more than enough.
I don't blame you for considering switching to British, OP. You've reached the crossroad that many have. It won't make defending against other Brits any easier but you do you.
As for the Germans, if there really are going to be ''several'' more ages then they'll eventually be overpowered too. It takes awhile to really get them going though. They were awful for me up until mid-EA.
My main account is French and I'm with JMoney. If they changed French training times or training blessing I'd probably quit. Especially since the advent of the silo and the continued addition of multiple traps every age that kill all atomic units but tanks, paratroopers and helis regardless what level the traps are.
I have a 197 AA French, 121 IA German, and 77 GPA Brit account. The training times on the lower accounts drive me nuts, particularly during a blessing, but at least in those ages I'm not forced to play for an hour or more at a time just to get ahead. Playing one battle and hoping to not be attacked during rebuilds just doesn't work in AA.
French, Germans, Koreans, Chinese are fine, imo.
Brits are overpowered because of their range and the fact that shooters in general provide by far the most bang for the buck in this game.
The Greek tank is ok, as far as units go. Though tanks suck at attacking. They're just meatshields so the French tank is far superior in that regard. The Greek power is a joke. Instead of 5 minutes per age it should be a 1% reduction per age. Global is the tenth age I believe so by then a 2 week upgrade would be:
336 hours- 33.6= 302.4 hours or 12 days 14 hour 24 minutes. Not OP but certainly appealing in the context of dozens of upgrades per age.
Romans will probably get screwed again by no barrack upgrades during a future age. Honestly, I don't think this game will be able to handle too many more animations and units to track. And as that's their ONLY ability (their unit is the worst in the game) they need a boost.
The Japanese........? Hoo boy, I wouldn't even know where to begin.
However Moctezuma's capstone is clearly designed to take the easy way out of the no NTG issue due to nation imbalance. So join the party, switch to Brits. Why the hell not? They're never going to do anything about them anyway. Again though, it's not going to make defending against them any easier, though you may glean some insight by alliance challenging yourself.
Sorry for the novella. Winding down for the night. Feel free to tl;dr.