With the other thread talking about the changes to tech speed in relation to map size, and this thread seeming to having the take that tech is already fast as it is (which I agree with imo), I think it would be fair to keep the values for the map size the same, and maybe even increase it a little. There was also some talk on a per era scale for science cost, which I can see the value in because yes as a game goes on generally you will have more and more cities. Much more so in higher difficulties as it becomes more & more necessary to war and weaken a snow-balling AI. Though and perhaps I've missed something but I also fail to see the purpose to this when you can just increase the base science cost of the techs themselves. I also saw keeping the values the same across map sizes, which I have to disagree with here because with more space also gives more time to settle before you have to start pumping out units to protect yourself from your neighbors. Maybe the disparity shouldn't be as big?
I've started 3 games on this patch, 2 to industrial and 1 to modern, and I too found that tech really does speed up in renaissance, if not industrial. Policy choice as well but I figure this is by design (I finish the 3rd tree way faster then I finish the 2nd or 1st, in probably half the time). It's hard without more testing to know what to contribute this to, but a common theme in my games was always to work Culture -> Scientist -> Diplomat specialist first. I know there's spies too but it's not just them, techs take a noticeable quicker amount of time to research. I think polices contribute a lot to this science gain, but it's hard nerfing them in any meaningful way without completely changing how they give science. The free scientist from oxford university is also really nice. All three of these games have been wide games (8 cities or more) so tall players may have a different experience.
I've thought about a few small nerfs in hopes of slowing it down; academy gain in physics to +2 instead of +3, Armory down to +1 (as even the military academy only gives 1), reducing school of philosophy golden age gain to +15% (golden ages seem pretty common around this time) or completely changing bank's science on purchase ability (but then renaissance would lose it's one and only science building). Really though, and I'm kind of kicking myself for not having seen it sooner then the time of this writing, I think the real offender here could be one thing in particular, in a little tech known as Scientific Theory. 2 very powerful buildings here (even if one is terrain dependent) but see, unless you're a weirdo who cares for the paltry 1 science on the military academy or happens to have a few embassies, unlike every other era, for industrial all the major boost in science take place in this one tech. This on top of expansion being pretty much over (no more increased science cost) and amassing enough GG's to really start expending them for citadels, just to name a few. I think it speaks for itself really.
To clarify, Scientific Theory gives you the public school, +1 to scientist specialist, and +3 to academies (and tech trade if enabled). In any other era these 3 bonuses would be spread out across 3 different techs.
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