For gestures/swipe-typing I do know that all 3 have that feature
unfortunately I can't provide reviews on it as I still tap to type, haven't had time to retrain unfortunately

For Florisboard's features I really like their sea of options for customizability:

• it gives me Arch Linux vibes as it give you plenty to fiddle around with like:
  hinted symbols/number row, built-in Incognito mode, undo&redo, built-in dev tool toggles, customizations backup&restore, etc
• gripes wise is wanting remap keys but this is such an insignificant gripe considering all the features they've implemented
  • I'd imagine that this is a potential feature down the far future

For Unexpected Keyboard, the features it provided was actually unexpected:

• like I didn't expect to get a Ctrl, Fn, ESC button, like wtf that's pretty awesome!
• it also has a single button arrow d-pad!
• essentially this has all the keys on a desktop keyboard
• gripes wise I wish there was a language indicator for when I'm switching between dvorak, qwerty, and Korean
  • this is also a very small nitpick that will probably get implemented later on

I haven't used Thumb-Keys but I've seen good reviews about it so it's worth a shot as well 👍