I've always hated Xiaomi's custom UI despite their great hardware. Huawei was a good balance back before the sanctions, though if you can't live without google stuff Honor phones are the "successor".
oh, they're super-assholes about it, no question. there's absolutely no reason why it should take that long. but at least it's possible. learned the other day that samsung is also locked on all modern models; that used to be the go-to solution for a hassle-free CM/LOS solution.