But...more personality? Fat Boo was a manchild even more so than Goku who loved to eat candy, and his appearance completely belied his true (or so it appeared) nature;
Fat Buu had way more depth to him than the generic short-tempered smug thug that was Freeza. He was very unique among the Z villains.
we didn't get enough of the Grey Boo to determine crap about him;
Grey Buu is Super Buu.
and all the forms of Super Boo basically cackled like a maniac and fought
Did you miss the scenes where he sat quietly and waited? Or when he got impatient and freaked out? Or when he screamed about candy? Or when he was a smart ass to Gotenks and Goku? Or when he made plans to get around his enemy's strength advantage? He did not just cackle and fight, there was plenty of personality to him.
save for his post-Gohan-absorption state, who seemed to take on an air of arrogance, that seemed to harken back to Cell, and...*gasp*...FREEZA!
Quite the opposite, given that he tried to stop Goku and Vegeta from fusing, while Cell outright told his opponents to use hax methods to get stronger than him. He was just confident in himself (note: that's different from arrogance) due to his recent string of victories after his planning. Freeza himself is just a repeat of Vegeta anyway, and he's composed entirely of stock villain traits, so calling anyone else a call back to him just seems silly.
I don't dislike Boo, but I think there's a big reason that, for all that he achieves compared to other villains, he's not remembered nearly as fondly by most as the charismatic Freeza is.
Freeza's not charismatic. Charisma means he has a charm that inspires devotion and loyalty. Freeza doesn't inspire devotion from his henchmen, he just threatens them if they don't do what he says. Even then, they frequently betray him (Nappa, Vegeta), spit on his memory (Cold), or offer to betray him (Cui, Zarbon). There's nothing to him besides his power level, which is way higher than everyone else's for no reason.
Plus, Buu, Cell, and Vegeta all beat him out on the only Japanese popularity polls I've seen IIRC.