Frieza was only 'wanked' in Resurrection 'F'. Every other time he was brought back, he was the butt monkey and the 'you used to be the best, but now even the kids can one-shot you'. And it can't be too long since, guess what, Frieza is still popular and people are excited to see him. And 'bad writing' for something you haven't even seen yet. Gohan jumping several tiers in one night because 'his special' his questionable writing, but that's okay because you like Gohan. I should also point out that it was never said that "Freeza was supposed to be the character that couldn't be redeemed". That is what fans concluded and we know how fans' ideas have been proven wrong several times.
Buu falling asleep is pretty much a running gag, which flies over the heads of everyone for some reason. It isn't a 'cheap cop-out', it's literally Buu's gag like Roshi being a pervert.