#1: I feel that Ayers will be replacing Tuck, in that Tuck was one of the best run defenders in the league from the DE position last year (JPP as well). With the new secondary we have, having freakishly athletic pass rushers is less of a concern than just getting guys that can contain the QB in the pocket and prevent rollouts, and from there get a coverage sack. Being able to shut down the run and maintain gap responsibility are more important now.
#2: I agree, Schwartz is a HUGE upgrade from Boothe. Still wish Boothe could have been resigned as a backup, but alas...
#3: OL has definitely been upgraded, and I could see the likes of Swanson in the 3rd.
#4: I actually agree with the OP on this one. Donald would basically just be another Jenkins. That's good if you want to replace Jenkins (he is getting up there in age), but we could find a project later in the draft to develop and save the first rounder for a more need position like TE or WR. Don't get me wrong, I wouldn't mind the Donald pick, but would be a little peeved if we left Ebron or Evans on the board because of it.
#5: Evans would more closely resemble a Nicks replacement, and in the past week or so he has become my top choice if I had to choose at 12, though on the other hand he'll likely be gone.
#6: You DO know that TE is the thinnest position on the roster, right? We can field a complete defense with just the players we have now, not so for offense, who need a true wideout opposite from Randle and a tight end. A guy like Donald is value, a guy like Ebron or Evans is value + need.
I agree with pretty much everything you said above, especially about Donald. The defense, as it is now, could play today and play very well. The offense, however, would struggle to be much better than last year IMO.