Not sure if this will help you, as you say your skin is sensitive to waxing. I ended up actually plucking my pubic hair (only the coarse part, on top of the mons), which does essentially the same thing as waxing. This will leave some bumps the first time you do it, but you should only have to do this once and the bumps will not last very long. With waxing (or plucking) the hair comes back finer, and some hairs will actually not grow back at all (just like with eyebrows). Now that the hair is finer, it should be very easy to shave, in fact getting a close shave by shaving in the opposite direction of hair growth is now possible. I only recently tried this so I don't know for how long I'll be able to keep this up. But I only waxed/plucked once, and so far with shaving I have had no irritation, and everything is completely smooth. I believe this is the secret all those porn stars and strippers are using, they just won't tell us...haha. But really, I'm not sure if this will work for you, but I highly would recommend this.

In sum:

-waxing=bad because you have to grow it out, therefore you're not always smooth. And as you say, it irritates you so this would be a pain to do every few weeks.

-shaving=bad because it always always always will lead to irritation (no matter who you are) unless the hair has been made fine by waxing.

Re: plucking, I had some free time and managed to pluck every hair off my mons (the most coarse hair that refused to behave with shaving), it's possible this might leave you less irritated than actually waxing. (note that waxing and plucking do the same thing to the hair). Although I do have to put the disclaimer that plucking did leave me slightly irritated with some bumps, but nothing like when I shaved, and the bumps didn't last very long.

Hope this was helpful and not too rambly