I'm hesitant on this.
Well, as hesitant as I can be for a Star Wars film.
I'm not particularly convinced that JJ is a strong enough director to do the ending of this trilogy justice. He's a solid 7/10 director and I can see why Disney would give him the first movie of the trilogy. He makes unspectacular mass appeal movies. After the prequels I think that was attractive to Disney because they needed a widely liked base on which to rebuild the franchise.
I don't think he's particularly suited to finishing telling a story though.
I also think that this was the wrong franchise for his slightly scattergun "mystery box" technique. It's an incredibly lore heavy franchise. If you start throwing around things like knights of ren/reys parentage/why luke is a hermit/snoke's identity/rey's force flashback if there was no set plan on where they were going, though that's more the fault of the creative team than JJ I suppose.
Actually marry me.