Re: Just Drop[ped]Box. new three device syncing limit is unworkable/pathetic, 5 minimum needed.
I've been using Resilio Sync ever since Dropbox lost three days of my data. Fortunately it was a simple task to recover, but it put me off Dropbox forever.
Resilio Sync is strictly peer-to-peer and not perfect, but even the free option is quite useful. It also has options for eschewing their relay servers and so on if you want to keep everything off their systems. Your Paranoia May Vary. :)
I use something called Gadwin for the handy screenshot capture feature that Dropbox had. Also has a useful free version.
I consider both worth the cost of buying the pro versions and I like to support products that work for me so I have done so. YMMV.