Battle Tree Team Suggestions/Criticism

Hey, all, I've been trying to make a good Battle Tree team, and I've capped out at 14 wins in Super Singles. I was wondering if I could get some feedback on my team, and see where I could improve? Here's my team, so far:

Cloyster

Naive/Skill Link

Focus Sash

1. Shell Smash

2. Razor Shell

3. Icicle Spear

4. Rock Blast

Dragonite

Adamant/Multi Scale

Lum Berry

1. Dragon Dance

2. Outrage

3. Earthquake

4. Fire Punch

Mimikyu

Jolly/Disguise

Red Card

1. Play Rough

2. Swords Dance

3. Shadow Claw

4. Shadow Sneak

My first though is that I'm not really being helped too much by Dragonite - he's good, but maybe a Garchomp/Salamence would be a better upgrade? Is it time to drop Cloyster?