You have a bit of a weakness to physical water, grass, and rock moves as it stands, that could be patched by swapping Mamoswine for Ferrothorn as your SR laying tank.
Ferrothorn@Leftovers
Iron Barbs
Relaxed
252 HP, 48 Defense, 208 Special Defense
-Stealth Rocks
-Leech Seed
-Power Whip
-Thunder Wave