In terms of cost I would think a few small cameras, don't have to be HD, would be just the ticket for monitoring start up. (Yes, I know, aviation standards!)
Don't know what a tug costs per push but if there is no airport mandate ("HAVE to have a tug") then I imagine the savings would really stack up over time.
I am a little surprised no one has arranged for wheels to be spun up for landing, but maybe the hit on the tires each landing isn't worth it, might be another saving there?
Just thinking out loud.