My personal Tier List
Wanted to share my own personal tier list.
Generally S tier are the cookies you want. I'd argue you could easily beat 90% of the game content with just these cookies.
A tier are really solid, and will likely have prominent roles in the meta, including guild battles, for example.
Like A tier, B tier cookies are really good, but maybe just show up slightly less in the meta. Still, you'll want to power these cookies up if given a chance.
C tier cookies are generally good and useful, but aren't widely used, and can probably be replaced most of the time.
D tier cookies are basically bad cookies that are generally a step above F cookies. If you've got the resources, sure, power them up, and don't feel bad about it, but don't be surprised if you basically never use them.
F - don't bother putting any resources into any of these cookies unless you just really want to.
Hopefully this will help folks who are like "Should I power this up", or "Which one should I get?"
FYI, I'm in the top 0.3% of the game, so I generally know what I'm talking about. :)