The Missile Launcher in the scout squad can use Telion's BS 6. Try missing with that.
The tactical squads can combat squad and take your assault half (PF + Flamer) forward, or as you wanted to be able to blow stuff up and hold off rushes, you can use the razorback to support the tactical squad. (Just cos it can only hold 6 models doesn't mean you have to try and put any in it.) So you end up with ten marines with a missile launcher, a flamer and a power fist, with a twin-linked heavy bolter in support.
IMO Vindicators are the best marine tank next to the LR/LRC/LRR