I'm working on an AU PROJECT with something similar, but there are a few difficulties, particularly regarding ECM. Encountering a field shuts it down right when you need it, like dropping a mini into water, so you need at least 2 ECCM fields to prevent it.
They really can support infantry in the anti-Elemental, tanks, and mech roles, but it gets riskier on the attack. I find unexpected roles - where the drone operator has surprise are where they are best used, but beyond scout and fire support there aren't many safe roles for them.
They're perfectly fine for service roles, like rear area servicemechs, freight and cargo, stuff like that.