I think a donation fee is ok. Its fair to give developer a share, and this way everyone donates proportional to their "income".
5% is not okay though because we have electricity to pay for too ...
A miner which gives you 2x the speed of regular one (if any!) and you think 5% is too much?
Don't use it then.
Its a win-win for the developer AND users. Until better way to reward devs is found
we have to cover electricity costs 5% is too much and he charges that much because he knows we don't have any other option, if i'm not going to profit (electricity is 80% of my mining revenue + 5% dev fee + 2% pool fee) after paying for electricity then what is the point .....
also 2 x faster 100 x faster difficulty will normalize that when everybody starts using that miner
devfee should never be over 1 ~ 2 % as a maximum because tons of users will be using that miner and hash for him at no electricity cost so why be greedy, i mean the dev will still end with a huge amount of electricity free hashes ...
Honestly, a dev for a miner will get more at 2% or lower dev fee, because people will more likely give a donation that will surpass the 5% from the richer miners/investors. This is my opinion though.
Noooooooooope.
(actually those who give aren't generally the big whale (who have to pay their electricity bill and pool fee... good one ) but rather the small users, or some coin supporters in some case... the community doesn't show a lot its appreciation... )