I disagree with the boss trials, it's better having your own room, you won't have to fight over the boss. Would you really be okay with some random person getting a boss drop with the prices they're going for now? No, I don't think so. I know it was all about "working together" back then, but if you go in to lets say, Soki, and one of the random people you were working with got a staff, how would you feel? Most people can 1hko the bosses, would it really be fair to go hunting and waiting for it to spawn, and some bunny or buffalo comes in and kills it in one hit? No.
As for trials, most are fairly short, no reason to complain about any except for Dread. Dread is just awful.
And now angel system, if people aren't going to answer them, they shouldn't have it turned on in the first place.
I'm content with all we have already, I wouldn't like to see anything removed.