Bounce is the more curious record and more interesting to dig into, whereas Crush is better as an album, as it flows much better and has a more focused theme. It's tough to decide, though. The main portion of Crush indeed sounds like late 90s pop rock, but decidedly safe so, and while executed well, it's not as curious as the more unlikely borrowings of Bounce (7 string riffing?). Also, while it is a more focused record, Crush is also half a solo album as well, so the band unity is hardly in place. And the one problem Crush has is that it's basically IML plus album tracks. The rest of the album sounds way different.

Also, no, you cannot combine the two to make a great album. Bounce's direction is scattered enough as it is; Hook Me Up or Undivided would sound seriously out of place on a "Crush +" album. I guess you could add Misunderstood.

I dunno, to me it's down to:

It's My Life
Thank You For Loving Me (best power ballad they did after the 90s by far)
Two Story Town
Just Older (but mostly due to its status; not the biggest fan myself)
One Wild Night

versus

Undivided
Misunderstood
Right Side Of Wrong (better "epic" track than Next 100 Years IMO)
Bounce

On the other hand, there's more track on Crush I don't care about at all (I Got The Girl, She's A Mystery, Save The World) than on Bounce.