I got my hair cut from about shoulder-length to a fauxhawk style a few weeks ago, and it works really well for me. But I've got a good face shape for it.
I definitely think the first picture would look better on you than the longer hair, since your face is more round. Since you seem like you want to make too many waves, you may want to ask for a pixie cut - which is pretty much the female version of the first pic you posted. Pixies tend to look good with round faces, and can be made masculine pretty easily - and it's a good, safe option if you've never gone that short before.
Hallie Berry had this great pixie for a while:

You could ask the stylist to box the ear area a bit more (pointy 'sideburns' are very feminine, boxy ones are more boyish) and if left a little longer on top it could be easily fauxhawked. Or bring a picture of a pixie and the first pic you posted and say something like "I want this pixie, at this length."