May I suggest that 'my head is a weird shape', is more a matter that you've not seen your head shape without much hair before? Thus the 30 day rule. Now is a good time to shave with a razor. Give it a week and you'll be back to the 0 clipper, if you don't shave again. However most guys really like the shaved feel and look. It sure is worth a try.
I have dips on my scalp. I just figured out how to work through them for a smooth shave.
Yes, your hairline is receding a little, but looks like overall you still have a full head of hair, so I'd call it BBC. That's where I am and a good choice. Hope you like it.