There needs to be a flying troop that can avoid mortars and cannons, but still be affected by the top gun on the gunner tower. Bunkers could be set to air OR ground, so as a ph5 i could have 1 set to air and 1 set to ground. This would also make sky raiders with brutes and gunners less op. But of course theyd need to be a defence to go with it, like a fireworks stand or something
I don't think they're Over Powered. I get blocked with even collectors all the time. One or two Mortar fire because they landed in the wrong spot and they are done... Plus, there are lots of creative bases that block Skyraiders really well. After they land, they have no special ability. I can't say I agree with you.
I agree with @hidyhorum there are lots of ways to make sure the skyraiders can't land near your "hotspots" (mortars and groundpounders). I personally think we are good for now with air units.
I'm with hidyhorum and The Fish Eyed Pirate. I use the sky raiders regularly, but the are easily blocked and once on the ground very limited. They are a fun novelty. I'm far more interested in more ground, or maybe water based pirates, something that we could control instead of the current AI would be nice.