I would agree this is a better overall team than going into last year. Mostly due to the large increase in reliable SP depth, whereas last year was a crapshoot after Peralta. Essentially the same BP since Devin didn't play.
I put no faith in that 3B combo you list and am just hoping for basic "dont be awful" out of the position, so obviously that's a step down from what Adames provided last year. But add in full year Chourio, hopefully 50 more games from Yelich, along with likely slight improvements from Hoskins and other young players like Ortiz, Turang, Mitchell, Frelick and it should come close to balancing Adames loss. And you'd come out ahead if someone like Mitchell really takes off.
But like you said, will the luck and chips fall in the right way like they did last year, who knows. Division is better and we got lucky with some pitcher pickups that hit last year, will they do it back to back years? Will injuries playout in an ok way. Adames was very lucky with his HRs being a ton of 3R shots which essentially won games, so can't bank on that again. By no means saying lock to win the division as the Cubs have improved, but I'd definitely take the over on our 82ish win total.