Not scared of it, it's just a bad idea. Will make the mech very much more vulnerable and destroyed much easier. Keep in mind, the bulk of your firepower is in the arms and side torso on that mech. By reducing the CT, you MUST increase the ST or destroy the mech model. The CT soaking up the damage allows your mech to retain it's offensive capabilities for longer than other mechs(there are a few) which are notorious for losing their ST's.
Also, stating that torso movement to spread damage shouldn't need to be done is ridiculous. If you want your mech to remain effective, ANY mech, you should twist. It spreads the damage out so that you don't get any one component focused more than the others increasing your over-all survivability.
To your statement about being swarmed by lights and killed. They do that. Lights shouldn't be a problem if they are alone. In packs, even assault mechs should fear them. That is a lot of highly mobile weapons circling them, very hard to hit, and multiple targets will usually overwhelm a single mech of any kind. If you are having trouble with light mechs, stick closer to a group. You are more likely to get more locks and have a shorter flight time for your missiles. Second, get on a team that will cover their support mechs. If you have a team, and they won't cover you, they are not much of a team.
Edit: It's pretty much a design fault in the mech it's self since the first design(not just PGI's concept). Anything with a protruding CT is going to get CT'd faster than most, deal with it.
I don't think there is an expiration date. I saved my free valentines day premium for over 6 months.