What should I not check for the first tier? second tier?

mishav

and should everything be checked for the 3rd and lower tiers?

Sven

Could you please stop opening a thread for every thing? This is all covered by various other discussions about tiers, optimization for LpM and so on. Beside that it's all a decision that someone has to do on it's own as there is no 1:1 solution for everyone. It all depends on your website and the needs for it. SEO is not some blueprint (if thats the right word).