Maybe this will help a bit. Keep in mind these are averaged out and not promises for future rewards... They are based in real rewards but where I start going into per month and beyond those are based on projections of what I had already accomplished. And as for extra hashing being added I believe you'd see more of an affect on Slush than Kano because when they started topping 2 Eh/s on Slush my rewards (small to begin with) shrunk a lot. Again, if you're finding more blocks then it all evens out.

Kano
https://www.dropbox.com/s/s549pf1o7fmavne/ResultsKano.jpg?dl=0

Based on blocks found since I started and got paid an average
3-S9s    0.02386137 BTC
1-S9    0.00795379 BTC
Per Th/s    0.00058917 BTC
Only based on the last 13 blocks found.

Slush
https://www.dropbox.com/s/ubrqs67y846irly/ResultsSlush.jpg?dl=0

Average block reward on Slush for 40.5 Th/s was 0.00036331 BTC
Based on 152 blocks found