Few things I noticed if I was attacking and came across this...
1. Too many rocket turrets, burst turrets are better as the majority turret type. They have 120% damage vs bruisers and jet troopers. A few are nice to target vehicles, maybe 2-3 burst to every 1 rocket turret.
2. Mortar Turrets are pretty much a waste at the moment. Won't fire on jetpack troopers, do squat for damage vs vehicles. Turn them into burst turrets for reasons listed in #1.
3. Never upgrade your base to 2 or more levels beyond your turrets. Rushing will leave you extremely weak and an easy 3-star since at this point you are facing up to level 10's. It's tempting to rush to unlock that one unit type (like jetpack troopers) but if you do you will lose almost every defense for at least a month to two months while you play catch up leveling up your turrets all the while losing a lot of resources to defense losses that you need to level them up in the first place.
If I was attacking this base I would drop Luke/Vader behind a resource side (whichever I needed most, usually alloy) hit his special and while your turrets fire on him fruitlessly I drop in rest of the attack force to clear out the base. Your turrets are slightly grouped together which when they are up to appropriate level will help, vehicles/soldiers attack a nearby turret the others can attack them.