Always love reading new hero design concepts, and I think your idea is really interesting! Having all abilities tied to a drone deployment sounds tricky, but interesting to play around with.
I will say though that 5s of lockout from weaponry is pretty extreme, as primary fires are vital for the enemy to defend themselves. Without it, heroes like Cassidy, Reaper, Pharah, and Zenyatta are pretty much dead. I think for a support, just causing their weapon to deal ~20% less damage would be enough.
Otherwise, really like the concept, and the thought put into it!