I left Slush for a number of reasons but here's one of the biggest...

When the pool was 1.52 Eh/s I was getting an average reward of 0.00050955 BTC for 40.5 Th/s.
When the pool was 1.82 Eh/s I was getting an average reward of 0.00036331 BTC for 40.5 Th/s.

The Slush pool is now over 2+ Eh/s so I can't even imagine how much smaller my payouts would be at this point. With my very limited actual results so far on Kano I am seeing an average of 0.02263097 BTC per block found. This is why I jumped to Kano although I do have some concerns if the pool shrinks. If it grows then of course rewards will as well but hopefully that helps us find more blocks as well. I would not change the ramp because it rewards the loyal and not the pool jumpers.