The laser is very plausable in near future
The MoD are working on a anti-mine laser for on tanks.. It only works with onts that are near the surface.. I read about it a year or so ago, so they musta advanced a bot by now
For the missile laser, you could get the script for the "Missile-make-miss" thing, and instead of diverting the missile, setdammage it, and make the laser line thing...?
Dunno
The UAV thing is, well, not simple, but the scripting stuff is not to hard..
You have the UAV circle the tank (A really controlable heli?), and if the tanks dammage is under 0.5, it lands near the tank, and repares it
- Ben