without looking up their age etc...
- very nice backup PG. I would keep, but train passing up to at least prominent, sensational would be better. Can play as starting PG on your cup games.
- starting SF has no D, and not enough range, plus inept IS. I would sell and upgrade.
- starting C has not enough IS, and not enough ID. I would upgrade and move to backup C position.
Just my thoughts - by no means the absolute correct things to do, but hope this helps.