For those who say, "Why wouldn't you max collectors?" It's because it wastes time that could be used upgrading more important buildings such as barracks, defenses or other buildings. If you can farm enough resources to constantly keep your builders busy, then don't upgrade collectors. I'm my opinion, max lvl collectors only make a big difference at TH9 and TH10, since the upgrades are way more expensive and very long.
For that reason I'd say upgrade the TH, then do collectors while it's upgrading.




