I'm playing through as Air Raider and I prefer to use the limpet guns (because that is the closest I can get to using him like a Ranger I suppose). The guns seem pretty weak - I'm able to take on some early levels on Inferno but later stages on Hardest are wiping out my 4000 health. I'm preferring the chain limpet gun (24 locked & loaded!) but will there be a stronger flavour for me later on?
I HIGHLY recommend the wire guns over limpets. Limpets fire slowly, reload slowly, and it's quite easy to end up blowing up yourself or an ally. The only limpet guns I ever use are the snipers, if it's a level with transports or hectors & I'm waiting on a vehicle. The trick to wire guns is to fire & roll. Each wire can damage an enemy, so the more wires that hit, the more damage, and more wires will hit if you move. When dealing with bugs, fire & roll to the side. Preferably in a circle around the bugs. I usually manage to herd them into a nice circle (of death) while doing this. If you're fighting drones or bees, the skytrap wires are your best friend.
But, to answer your question, there are powerful limpet guns, but even the best ones are comparably low damage. The AR's primary offensive weapons are air raids & vehicles. --- Protecting the green Earth, if even for a single flower.
Thanks for the tip regarding the use of the wire guns. I had read that they were meant to be good but I found them (well, the ones I had) to be rather ineffective and stuck with limpets... but I noticed I had another (level 26 - 50x24) which I tried last night and WOW! I took out Crimson on Hardest with little trouble (Health Caravan vehicle and a ZEXR gun turret on standby though).