Here is my personal build for my C1. It happens to be my favorite mech I own, next to my Muromets. It runs a little hot if you keep up the Mlas fire along with the LRM's, but I have found it easily manageable.
Welcome on Mechspecs. First thoughts: - 4t is kinda very low on ammo (on mine I load 8 tons, and I happen to run out); - not sure 4JJ are mandatory; - BAP would be a great asset; - XL270 is a very odd choice of an engine. => downgrade to an XL255, drop 3 jets (one is enough for basic mobility)(your priority is to shoot missiles, not to jump around) and shave little armor in order to load ammo and BAP: If you're confident with less armor you can shave one more ton to fit more ammo. Personally I'd trade a MLas for a TAG, but that's another build.
Thanks for the tips. I put a 270 XL in because it filled up the tonnage after I allocated the weapons. I had thought of dropping some speed for more ammo. I do usually run out, even though I am sparing in what I shoot at since I hate wasting ammo. Does the BAP do a lot for missile boats? As to why I have 4 JJs; with the change to the way they work I like the maneuverability of 4 vs. 1.
It does a lot, and in my opinion is a requirement for all LRM-boat. It reduces the time to lock a target. It also counters ECM at short range, so you still be able to lock and shoot homing missiles instead of being jammed. It also increases radar range.
BAP is a must for LRMboat and StreakBoat. Counters one ECM, allows faster lock time, and longer radar range. IMO 1000 missiles is minimum requirement if you choose your shots, I prefer more. TAG is an acquired taste. It does allow for better locks and homing only when target is within LOS, although it does negate ECM. If you prefer +A, remember this upgrade work best under LOS. I suggest AMS, in the case ou get counter-lrmed you get some protection. This would also contribute to the general AMS umbrella of your team. For ease of use I would suggest the build below. It has less direct MLas support, but much better at LRMing.