In my experience, Tox qua qTox and Toxic has been the most stable of the options you've listed. Retroshare is another fine (though perhaps fiddly) example, and

In my experience, Tox qua qTox and Toxic has been the most stable of the options you've listed. Retroshare is another fine (though perhaps fiddly) example, and it has the longest standing communities of any of these (I see about ~2.3k people right now), with plenty of non-voice/vidya features; it also works with i2p, not just tor.