One of the biggest things to remember about Rolemaster is something I often hear from GURPS players as well--"only use the parts you need".
Above: Probably not GURPS or Rolemaster players.
Let's face it: systems like GURPS or Rolemaster include far, far, more game than most people will need or want. But that's what you get with a toolkit system. Now, some, like Chaosium's Basic Roleplaying feature more of a "build up" module--here's the basics, now add what you need. GURPS sort of does this with GURPS Lite, and Rolemaster Express can also be seen as a basic, entry-level product. But the full versions of those games are more of a "here's everything, take what you need". In one module, the all the parts you need are on the shelves; in the other, the basic models are on display, but the accessories are just back in the stockroom. There's no correct model here; only preference.
There isn't a right or wrong approach, but I think that sometimes GMs worry about external perception of their game--that if they aren't doing Rules As Written, they'll be seen as playing some bastardized form of their game. I have played in exactly 1 Rules As Written campaign in the past decade--a D&D 3.5 outing, and it was atrocious. Too much research, too much retconning of resolutions, too much rules lawyering. When we admit that every game will have a certain amount of drift to it, I think we become much more open to looking at more games as modular toolkits. And remember: just because you've hacked a system doesn't mean that suddenly the rule of law will not prevail. If your group still favors rules more than rulings, a one-page houserule document can neatly indicate what is and is not being used.
It can be fun when you take a raw marble block of a RPG system and turn it into a well-sculpted, responsive personal masterpiece. I think it can also tell you a lot about your preferences for game play and as a Game Master.