Getting a fixed amount like $5 can be tricky because it will be abused by the players and the casino will either implement KYC which will mean the casino will miss out a lot of players as not everyone is comfortable doing KYC to an online crypto based casino.
$5 or 50% bonuses it doesnt matter which number you do prefer on because you would really still need to wager it off and also KYC thing is highly being frowned upon when it comes to that.
People will surely lost their interest and this is why majority here on crypto space gambling site doesnt really require such stuff.Neither of the two in terms of bonus then if i do need to choose
then percentage wise would be a nice option but overall im not really that a fan on getting these perks yet we know that these are just luring tools for people to lose in the long run.