I've been using the Elecom Deft Pro and Huge for a few years now. Huge I haven't used anymore for months. I guess I'll start there.
Cons of the Huge is, well, it's huge. The wrist rest area is awkwardly angled for my wrist, especially if I'm using ~~my stupidly purchased weeb mousepads, IYKYK~~ a separate wrist rest. It makes me put my whole arm way to extended. Otherwise I like the huge ball size. Speaking of angles, I never really tried to get wedges to bring the Huge more vertical. I did put a small wrist rest on the left side to bring it up a bit and do find it more comfortable.
On to the Deft Pro, cons would be I'd like it to be a bit bigger I think? Especially the ball, but it's functionally solid. Works much better with a separate wrist rest. Since it's small it's my office mouse that I lug around in my bag.
Both have started to get unintended double clicks. I never really have that much stiction problems with mine, but maybe my standard is low as these are the only two trackball mice I use.
Should I go with the ploopy classic? but I'll miss the extra buttons the elecoms have. not that I use it for anything important, mind you. I just assigned shortcuts to go left/right of tabs in my browser.
Maybe the adept? I never has a symmetrical trackball since the PS/2 kensington Orbit I knicked from my dad's stash that started my on my trackball journey.
Should I go with the gameball? Like I do game, but not in anything PVP or competitive.
Or should I just buy a new Deft Pro? I really don't have that much to complain. Even the ball size is a nitpick I could live with. The Huge really has to fix it's hugeness. So I wouldn't really buy it again.