Figuring out exactly what a given modifier should cost that’s not in the rules can be extremely trying for any GM – much less a new GM. Here’s a couple of tricks I’ve learned over the years as both a GM, a game designer, and a writer.
When it comes down to it the best way to understand how enhancements, limitations, and features work is by playing the game and using your custom modifiers. You’ll soon suss out if their worth it or not, which will allow you to weigh future considerations with more care. I recently heard someone say that GURPS was like a bunch of Lego bricks – and that’s not unwholly inaccurate. Knowing what brick to place where to give you the finished design you want is part and parcel of any game system that uses positive and negative traits, but it is especially true of GURPS where you can literally build anything. Though, like any system it does some things well and others … less well, I still hold firmly to the idea that GURPS can accomplish a nearly any bit of design or campaign.
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