Palaces academy isn't in the same league as the other clubs he's managed. It might be a good crop for Palace but that doesn't mean they're going to be premier league ready.
It's going to be a hard sell for him to sign any players of quality regardless of money to spend given their reputation as a club and current squad. Who's going to want to join a team with about 15 players on the books, the best one wanting out and the other injured half the season?
A blank slate is good in concept but id be staggered if he pulls it off given he needs a rb, cb, lb, cm, a townsend replacement, a Zaha replacement and then just general depth.