how many coins should I split into? how do you all set your diversification weights?

I've gone all-in on one coin and seethed when it was the only one that didn't pump. but spread across 10–20 and you can't manage it and everything's mediocre. how many do you usually split into? if you have a rule like X% majors (BTC/ETH), Y% alts, share it. people also disagree on whether diversify or concentrate is the answer