that are good for +7 (fixed)
And a single city consume 4 health by itself. 7 is way too small.
Besides, Prosperity tree is way too weak compared to Science or Industry trees.
The effortlessness of health later is a problem, but some of that may be poor choices on the part of players (ie going for health when that problem has been solved)
No, towards the endgame you get a lot of
without much effort, e.g. your cities produce less and less unhealth
as they grow, Magnasati gets stronger and stronger as you build more and more buildings.
If they changed the ramp up in food costs, then it could be actually useful to have specialists. (or perhaps change all +%Growth bonuses into +%Food bonuses)
Not really. I once tried to play by scientists specialist with no Academies. It actually worked (on Soyuz) but the biggest problem I faced was the lack of scientists slots. You simply can not have as much scientists as you can afford because too few buildings have scientists slots (affinity buildings included, I had all of them).
Academies spam is much more effective tactic.
Btw., current growth food costs are just insane, I had built ALL food producing buildings, had purity farms and weather controller above them and tonnes of production converted into food and still didn't had any city with 20 population.