Just wanted to throw this up here. I directly edited all of terrain files so that hills have a net +2 value instead of +3 (+2 hammers instead of +2 hammers +1 food), matching flat tiles. That seems to fix a lot of brokenness, and I think it's where the main game needs to go. Without that edit, a start with forested hills is 50% stronger than a start without, possibly even more than that if there are a lot of hills around. Forests still provide +1 hammer (25% stronger than a normal tile) but no longer are these tiles often as good or better than actual resources. I know Firaxis has had hills tuned this new way through all of the preview builds and it seems to be intentional, but after trying both methods, I'm convinced the old Civ 4 and 5 method was superior. The issue is that a forested hill that provides +1 Food +3 Hammers is not only overpowered but has no tradeoffs, making it possible to maintain/grow population while also building quickly. It literally functions as a bonus resource on every tile, and if you don't roll hills nearby, you are eating a huge penalty. By removing the bonus Food they have, high Food starts are actually somewhat competitively valuable. This of course makes the already long build times even longer so I reduced those too. Seems to produce much better game. As an aside, giving the bonuses of an Oasis to their adjacent tiles makes them coveted tiles, which I quite like.