I never used any with snaps, I always used ones with the elastic so it would stretch and move. There's a lot styles out there, sometimes you have to try a couple of styles before you find one that works best for your environment, weather/climate, etc. It gets hot here in the summer so having...
She's lovely!
If it's easier to catch them all and put the saddles on at night, then that's what I'd do.
If they are agreeable and don't mind handling, then do it during the day. They may still have a few scuffles here and there depending on personality, but most are too worried about this...
Pattern of feather loss in the photos would indicate loss due to mating and/or feather picking. You notice feathers come in, but then they disappear...they are getting plucked out. Pin feathers/new growth are tasty!
How much space do you have and how many birds?
A lot of the feather loss may...