Okay, change Seed Bomb on Cacturne to Bullet Seed to break through subs. Keep Sucker Punch, Spikes, and Drain Punch! Also, give him a spread of 4 HP/252 Atk/252 Spe
Keep Alomomola. It walls SD Samurott with ease and your team will appreciate wish support, trust me. :) I've had huge success with Alomomola, so I'm not sure why it's not working for you. My advice would be to only bring it in on physical attackers and keep it away from Electric, Grass, and opposing Water-types.