I'm not too sure about the idea of drones. I felt drones in EvE caused a lot of imbalances.
Firstly there's the obvious lag problems of adding 5 NPCs per player to big battles. And second I think it would cause problems between mechs and smaller robots.
Currently medium weapons miss a lot against smaller bots and thus smaller bots can survive in PvP to do their thing, whatever it is. In return smaller bot damage is a lot lower compared to that of bigger bots. Adding drones in the way EvE has them would cause mechs to be able to deal equally good damage to both other mechs and smaller robots. Especially since the speed differences between the robots are much smaller then the speed differences between the different classes of ships in EvE.
However an alternate solution could be the following:
Drone Launchers, using most of the Missile Launcher support skills, this weapon would launch small drones at enemies that would fire several shots over time before running out of energy and disappearing/self-destructing. Technically they would function like a stacking DoT weapon and the drones crawling/flying around the target would be a merely visual effect.
It would be a weapon with basically no Alpha at all but after 10+ seconds the maximum number of drones would be on the target and the DPS would be above that of missiles. Say give it a 3 second RoF ( both for launching drones and the RoF of the drones themselves ) with each drone able of 3 shots. Thus by the fourth shot the first drone would expire and the target would only ever have 3 drones on him at a time.
To me it sounds like an interesting and cool weapon system that gives the same feel as drones would but without additional lag issues ( a DoT on the target should take a lot less server load then spawning a new NPC ) and you'd still be able to make small and medium weapons ( just give medium drones a higher hit dispersion on their stats, but make their hit dispersion scale with Seismics ) as not to unbalance the relation between small robots and mechs.
The missile support skills would be explained by the fact that launching a drone in a better position would increase the damage, RoF and accuracy of it. While shooting a drone without skills would result in it landing in a bad position and thus be less effective.
In addition to that I think it's fair to add a second weapons system to the missile skills seeing as guns have 3 while missiles only has 1.