I had a similar idea:
* Teams can protect up to four players that (a) were on their roster as of August 1, and (b) are first- or second-year players with 9 or fewer games.
* Players must be paid either twice the regular PS salary or 60% of their 53-man salary, whichever is greater, while on the PS, and that salary is guaranteed for the entire season (unless a player requests his release).
* In return, the player bypasses waivers. So the player can be "called up" to the 53 when needed (and the player gets the regular 53-man salary for those games), without worry about losing him to waiver claims.
* This does not prevent teams from signing "protected" players off another team's PS. (Remember that you can't "claim" a player off a practice squad.)