I m not sure you ll get any significant difference regardless of what selection you choose. Pls correct if I am wrong but on average, there has not been that much difference between these polls, especially if you do have a really small hash rate chunk.
switched something yesterday and in the morning it was an improvement.
I researched all the pool and did an overall sum of blocks they find on a day.
From this i chose 3 pool to work with. maybe i am wrong or maybe not but will have to see after few days to see if trends still persists.
thanks!