Main problem is the user agent isn't per-site. There are several user agent switchers that work per site, and several that randomize, but im still looking for one that does both to actually fill the role.

From a "user agent tracking" perspective, random spoofing per site prevents user agent based tracking (though of course there are other methods) within a single session, without this feature it somewhat defeats the point as if you're on two sites within the same random cycle you'll still be user agent matched.