Gotta be honest... I do not see the utility of either weapons, nor would I take them over thier more standard counterparts.
Ah! Perfect!
Thunderbolt-TOW Missile
Game Rules
The Thunderbolt-TOW provides a gunner the ability to inflict the full damage of a standard LRM launcher while ignoring ECM penalties, but can only be fired from a stationary launcher. With the optical guidance system, however, the missile can be guided over terrain obstacles such as hills but restricts it to vehicle use. It is unable to engage BA, Infantry, and airborne targets.
The system allows players to make aimed shots at a +2 penalty, even when out of direct LOS, but depends upon visual conditions at the time of launchings. The Thunderbolt-Tow missile is vulnerable to AMS systems, and is hindered by Smoke and weather conditions (found in Tactical Operations). The Thunderbolt-TOW is the only missile allowed on portable turrets.
So an aimed shot without LOS with a +2 to-hit modifier as long as the launcher is stationary at the beginning of the turn. Explain optimal visual conditions, and clearly state the missile suffers the same weather penalties like regular LRM/SRMs, etc. found in TacOps. I also think ECM should mess with the camera feed.
Maybe something like, "The Thunderbolt-TOW missile can be targeted by AMS system, and is effected by ECM. The Thunderbolt-TOW suffers the same weather penalties as described for LRMs and SRMs in TacOps.
All Thunderbolt-TOW missiles traveling through Smoke and ECM must make an immediate 1D6 roll to determine whether or not the missile crashes into the ground. A result of 1-3 the missile crashes, on a result of 4-6 the missile clears the smoke or ECM unharmed. This roll is made because smoke and ECM obscures the controller's view and ability to guide the missile. In the event the target has active ECM, a successful roll keeps the missile straight, but unable to make course corrections.
As for the I-AC, I think the I-AC is a little over-powering IMO and could use a jam rule or some sort of negative effect when running in burst-mode.
Ok, let's do the I-AC first. It's one of the attractions for me in the RL system that there are no jams; mechanically, it's very simple and even the militia common in my AU can't screw it up. Ditto the RL rate of fire.
What about reducing the ammo available for those Bursts, making it a far bigger deal to do so? The other option is to increase the weight, something I think would reduce their attraction. There aren't a lot of units that could spare the mass for an AC (Ultra or LB-X) and this would give them something besides beams (the NC glommed onto Reflec armor as soon as they could).
Now, the TTOW. I don't want to get rid of the ECM-invincibility, because as far as I know, as long as the launcher would've be out of it it would have no effect.
The AMS systems can already target the missile without a problem - but I just found the weather rules in tacops, excellent! I'll post an updated rules segment with that later. What would you say to a simple gunnery skill to deal with smoke? Something like once per smoke hex travelled?
Come to think of it, although the NC use Inferno SRMs, I don't have a single, 'in case of fire it explodes' rule. I'lladd something about that too.