My only concern is I will get more frequent small rewards which equal to much expensive fees when I spend my coins
Humm what do you spend them as fast as you get each payout? why not just save up a bunch of smaller payments in one wallet intill you have a bigger amount to spend on some thing? Or is there some thing im missing about this???
When the payments are received as many transactions, spending them takes more bytes which requires a larger transaction fee to get accepted into a block.
But it sounds like Kano is already planning something

When you've built up a collections of small deposits, send it to another wallet as a low priority transaction using the lowest fees you can. It will take several hours but the wait is worth it. The deposit will be clean and ready to be used normally.

there is a free service from a different pool.
you put in the tx id of your send and they put it in the next block they hit.
So for instance I have 0.176 btc in many deposits on my kano.is mining address. my bytes are 2500
The fee would be 0.005 btc maybe higher. in order to get to a 200 sat a byte level 0.00000200 per byte
I would send it with a fee of 0.001 to lets say coin base. that is 40 sats a byte level or 0.00000040
I would then use the other pools service to speed up the transaction . Takes around 3-5 hours but I spend 0.001 vs 0.005
If I do this once every 10 days that would be 36 times a year I would spend 0.036 btc vs 0.180 btc in fees
once in coinbase they consolidate and if I do a send from them it is 220-240 bytes they charge .00044 to 0.00048 that is 200 sats
so they do not need to have the send sped up.