Re: not neccessarily very good at brown-nosing...
Yep. Been there many times and got a whole drawer of 'T' Shirts.
Those 'events' kept hammering home that I was not cut out to be a brown noser, shoe licker, oh sorry Manager.
One Manager kept marking me down at review time for 'having no ambition'. Eventually his boss wondered why this was. Said Manager was away at the time so he came to me directly.
Once I'd told him that I had no wish to be a bad manager and preferred being a pretty good techie, I got a nice pay rise and a personal note from this senior manager thanking me for being honest and that the company had too many manager who were average at best. My manager was 'let go' soon after once his uselessness came to light.