I want to rent miner and buy hash and send them to pool.

The thing is I want to do so only when difficulty is lower. Difficulty fluctuates and in general, the market take care of things well eliminating arbitrage opportunity.

However, once in a while I can buy hash at a lower price when an alt coin difficulty drops before "market correct itself"

The problem is most pool do not directly value share proportional to difficulty. Shares submitted during low difficulty tend to worth the same with shares submitted before.

I want pools that recoqnize okay difficulty is low, so your share worths more. Alternatively I want pools that make it easier to get a share when difficulty of the network is indeed lower.

Is there such pool?

It has to be PPLNS or something that is pool hoping proof.

Is there such pool?

I am looking for altcoins algorithm. Miningpoolhub is fine but I don't know whether it qualifies or not.