Ribbed collar advice please

I’m making (another) stocking stitch jumper and hoping to improve on the pattern. The collar on the pattern is garter which I’m not a fan of so hoping to switch out for a ribbed.
I haven’t reached the part where id need to knit differently yet so can’t show you what I mean, but I’m intending on casting off where the garter would usually start, then picking up the stitches once the jumper is done and ribbing a collar, that way I can rib all the way round instead of in 4 straight lines (across the front, the back, and 2 over the shoulder joining the front and back) if that makes sense?
The only worry I have with doing this as I am winging it a bit is that the top of the collar will be as wide as the bottom. Which I don’t want as it’ll end up folding over like a turtle neck. Would I be right, when picking the stitches up, to miss a few so it gets narrower toward the top and stays straight? Say pick 2 skip 1 and repeat.
I hope that makes sense.
Thanks in advance. Mark.

Take a look at this pattern which has a ribbed neck. It may give you some idea of how the sts are picked up and also the shaping on the front neck to give you a bit of a rounded front neck.

This video may help with picking up sts. it shows picking up in just about every stitch. I usually don’t pick up so many sts but pick up maybe 2 for every 3.