Let's look what the numbers are:
Losing 4 pitchers: Graveman, E Mitchell (prob sign pro), Pollo, Girodo
Signed 9 pitchers, maybe more.
So you can see the pitching position is getting a major injection of talent.
Infielders losing 4: Norris (I guess he will sign pro), Flair (tranferring), Frost, Frazier (pro)
Signed 3 infielders, maybe more.
Losing 2 catchers.
Signed 2 catchers.
Losing 1 outfielder, Renfroe (pro)
So we are losing 12 (if all the drafted players sign) players.
We have signed 16 but maybe will sign 1 or 2 more. Restocking the pitching staff is the most important aspect. See my page of signees/commits for listing.