I can't really see the blemishes in the photo very well, but the areas on your scalp that you've highlighted are exactly the same areas where I've been battling a very similar issue for the past seven or eight months. I used to shave my entire scalp but several months ago, I began avoiding the spots where there wasn't any hair anyway -- at the temples, where the blemishes were the worst. It didn't seem to help much, but I've recently noticed that when I switched shaving cream -- from Headslick to Aveeno -- the irritation virtually disappeared. Even though I wasn't shaving those areas, the Headslick would run down over them and onto my forehead. I think I'm allergic to something that's in Headslick, because the problem has been much less severe -- to the point where it's almost gone away.
I have had a couple of minor flare-ups -- not nearly as severe as what I had before and the bumps weren't really noticeable unless you were really looking for them at a close distance. For the past couple of days I've just been using my electric razor on the top of my head -- because I really am that bald now

-- and using the Fusion blade with Aveeno on the fringe area. The past couple of days I've been pretty clear. My theory is that the less hair there is, the susceptible the scalp is to irritation. So what I recommend is:
1. Wash your scalp with antibacterial soap (Cuticura or Neutrogena) 2-3 times a day to remove excess oil and pat it dry with a towel or washcloth.
2. Avoid shaving the irritated area.
3. Try a different shaving cream -- preferably something like Aveeno which is designed for sensitive or problem skin. You may also consider using an electric razor on the sparse areas on top and save the blade for the heavy-duty work around the sides and back of your head. Using an electric razor eliminates the need to put shaving cream on top of your head. The fewer things that you have to put on your dome, the better.
I hope this helps.