I had Bellboom until I switched to Beautiful Town I honestly think its best for me but I often question switching to Early Bird or night owl because those would make a lot of things much more easily done.
I started off with Bell Boom (for about 2-3 months maybe?) until I had way too many flowers to water and eventually switched to Beautiful. It's a shame we can't have 2 Ordinances at the same time. I wish they'd make one for villagers staying forever. =v=
I had the beautiful one then switched to the night owl, but after awhile of getting annoyed by dead flowers and weeds I finally switched back to the beautiful ordinance. I guess it's the one most needed! Sometimes however I wish you could have more then one going at once.
I currently have the Beautiful Town ordinance in effect. I grew a lot of hybrid flowers and didn't feel like investing the time into watering them all.
I had Night Owl at one point and wish I could use that one at the same time, but alas. I found it really convenient and better suited to my playing habits, since I still use the island to make bells and Re-Tail closes a bit too early normally.
I had the beautiful town one, but recently switched to night owl so I could start making some gold roses! A bit annoying, but I'll probably switch it back soon. Or at least after I get one of the weeding badges.