A warm welcome from me too!
And welcome to the forum.
Funny how you cursed those "damn genes" of your maternal grandfather, for it's a sentiment I'm most
familiar with. My grandfather was bald too, and though the balding set in around the age of 23 in my case, I was equally worried about making that move. But it turned out well and I've never looked back.
I'm confident you'll make the same experience once you start shaving. Apart from being a most liberating experience (you're letting go, and you won't have to worry about and wasting your attention on your hair)
it'll also give you a new feel about yourself, and it can be (and usually is) the beginning of a new lifestyle - the bald lifestyle.
Yes, I agree with the other guys, just give it a try. Though Paul's advice (to just cut it short) is a sensible one, I'd recommend you go the whole nine yards and shave it all the way. A very short haircut and a completely shaven head are worlds apart - and me, personally, I don't like a very short haircut on myself. Whenever I'm lazy and I don't shave for a week, I look at my head and it gives me the shivers. It's a totally different feel (and look) from being completely bald, and it won't provide you with a reliable "preview" on how it's going to be like being bald.
But then again, that's just me. Go with what you feel comfortable with, at your own pace. That's my final advice.
Again, welcome to the forum. It's great having you on board.