I was thinking about this recently. We've seen the FT% regress, especially the first year here, on almost all of our transfers. I think what you mentioned as #2 above is the primary reason.
So I went and looked it up:
Gilbert: Previous 76%; ISU 71%
CJones: Previous 75%; ISU 77%
Pav: Previous: 84%; ISU 73% (small sample size )
Holmes: Previous 74%; ISU 69%
Osunniyi: Previous 64%; ISU 67%
Jaz : Previous 80%; ISU 73%
Gabe: Previous 78%; ISU 69%
Ward: Previous 70%; ISU 46% (small sample size)
R Jones: Previous 48%; ISU 42%
Brockington: Previous 78%; ISU 78%
So leaving out the small sample sizes (< 30 FTs with ISU), there's been 8 transfers - 2 improved slightly; 1 stayed the same; 5 regressed between 5-9%.
Also, something to watch for next year - Gabe and Jaz both improved between years 1 and 2 at ISU, but not back to where they were before (both shot >86% in the year before their transfer). For that matter, Bob has improved every year here too, for what it's worth - in his 5 yr career he's 140-314.