I still use rep some of the time, so either I'm an idiot, or it is still a viable civic. --- ... ~~~
It's not idiotic to run it when you don't have towns and aren't in war prep. The problem is that it lacks the PULL of a civic that might drag you out of HR, PS, or US. If rep is adding ~100 beakers/turn to a 1000 beaker/turn empire that is also putting up 100's and 100's of

,

, and infrastructure investment, it might not even be worth anarchy due to the production hit...not to mention the new incentive to skip that civic path in favor of sci meth, steel, or rifling. It just depends.
To be fair, I never remember anyone using environmentalism in the unmodded game.
It was very niche. Its primary draw was that it damaged some setups far less than others and could be forced by the UN (say you're not workshop reliant but a rival is, force him out of SP). I wouldn't mind seeing it made stronger, even if indirectly by pushing up the electricity

boost on windmills. when you compare an environmentalism + electricity + replaceable parts (likely to have it by the time you'd be in the civic) windmill to a town, you start to notice something...

. Alongside the massive health boost it's no joke.
I wasn't sure what to say about the changes from raw

to a reduction in

, though since there are ties with GW there it makes sense. You'll notice that I didn't complain about the changes to vassalage, serfdom, OR environmentalism...all 3 of these were definitely rarely used.
Vassalage now has real potential late-game over FS or bur if you have a large empire that isn't town-reliant...hell, it might boost some empires more than pre-nerf rep...but the presence of towns or a super capitol + smaller empire or draft spam makes that choice a strategically important one.
Serfdom's tradeoffs are truly trolololol. I like it a lot. Again, this is something that won't materialize in AI hands but might in the hands of a human (slapping that

on farms is no joke, especially for FIN riverside farms!). When arguing the merits of +1

from a spec or +1

from a farm, keep in mind that in a lot of empire setups the latter is more common! Eventually there is emancipation pressure, and caste workshops and slavery (production) are real competitors, but again you can pull a lot of raw

out of serfdom all game if you set it up the right way.
Environmentalism I haven't had much opportunity to work with. As most games I play go military it's not a practical civic choice because it's either too late or out of the way of key techs to go killing stuff.
I liked your representation idea Karadoc of boosting the rep back to +3 beakers, +4 happiness in (however many) largest cities, and -1 happiness in all cities.
This is a TREMENDOUS nerf.

is very important in this game. That rep gets that

without much maintenance or

investment is one of its bigger draws early game. Currently, it takes 15 cities with a single garrison in monarchy to provide comparable

to representation. However, if you put a global -1 on it (which doesn't make sense with the theory of representation anyway) then suddenly monarchy starts to win in

10 city range (likely much sooner, as rarely do players wind up with 0 extra military units past 1/city), even if you don't spend any extra resources on military police. Any halfway-decent set up empire with a bur cottage cap and maybe a 2nd commerce city, most post-rush economies, and any FIN or GLH/colossus setups suddenly start to look hard at ignoring rep even if they DIDN'T need mids to use it X_X. It also turns into a TREMENDOUS drain for larger empires, actually weaker in raw

practicality than US in some cases. Ouch.
I don't mean to get you down karadoc. I like a lot of what you're doing in the mod very much. The look at the governor is just another thing that makes me smile, and you've hit a lot more than missed with the civic changing.