I'm perhaps slightly surprised there's not been another 3 or 4 European contracts, but other than that it doesn't really seem that contentious. The Japanese and American seasons are ages away: unless you were planning on going already I can imagine that neither of those groups would be keen to have you on the books until the season is much closer to actually starting.
At home, there's about half a dozen players with contracts still to be sorted: Dobbins, Kailea, Pincus and Ripley I think are the last of the locals to be sorted out, while Matty Proctor and Vaolini Ekuasi (who are playing for Wellington and Auckland in the NPC respectively) are still technically contracted as well to my knowledge.
A substantial number of the remaining Rebels players fit into journeyman, development, or extended squad positions at other sides: particularly looking at blokes like Jooste, Louwrens, Tuttle, Glen Vaihu, David Vaihu, Mason Gordon, Maiava, Hough, Strachan, Talataiana, Tuipulotu. There's very rarely a time when these players will be high priority signings unless there's specific gaps in your squad, or you genuinely believe one of these young guys is a gun: (see here, Brumbies signing of Tualima and Feliuai to cover the departures of Swain and Tua).
Which only really leaves the prop group (Talakai, Eloff, Pone) and Angelo Smith, all of whom you'd probably prefer stick around for tight 5 depth and development purposes, but presuming fitness of other players, potentially struggle to give a best 23 spot to: is that what blokes like Pone and Eloff want having played about half a dozen times between them being stuck behind the Gibbon-Kailea-Tupou-Talakai group all season?