One bass I absolutely CAN'T play...Thunderbird. It is not bosom friendly, and that's a perspective you just won't get from out male tbass members.. I am picky about upper horn shape from a comfort perspective.
That would depend on just how chunky the guy in question is and the size of his "moobs". Oh and no unauthorized crushing of "the girls" allowed.
Ok back on topic...
We could start with the obvious short scale stuff, or even a little box Steinberger, but.... those are a little too obvious. Just because the OP is a chick doesn't mean she should be stuck with a pink "Hello Kitty" Bronco. Besides if you decide to go short scale, you will have severely limited the options available to you. However if it feels right, then go with it regardless of what it is or who made it.
Out of the basses I have, the most comfortable one by far, due to the small neck and mid sized body, is my Squier P-Bass Special with the P body (It's slightly thinner than a Mexi or US P bass) with a Jazz neck. For a full size instrument it is quite light weight and does not wear out my shoulders, wrists, or hands after hours of noodling. That being said, I also play 6 strings, and I'm 6'3 with ape arms, so what do I know?
Ibanez would be my first serious suggestion. Ibanez has always had the smallest/slimmest neck profiles of the major off the shelf brands, and they are quite prevalent so they are easy to find and try out. In addition, the SoundGear line has some very curvy bodies that are quite comfortable, especially the satin finished models. The SoundGear line is also one of the most diverse so you could get PJ's, dual J's, big humbuckers, and all sorts of electronics options. This would be my first stop.
I tried out a Carvin Bromber 4 string and they have a very thin neck profile from front to back (fretboard to thumb). It is smaller than their regular 4 string neck through profile and was almost like playing a Strat. Yes I am a bit of a fan boy but I'm just offering ideas. Of course any sort of custom order bass will give you options.
If you can find one a Danelectro Longhorn. It may not be "your thing" but they were super light and had very slim, easy playing necks.
If you're feeling brave, you could try a kit or Warmoth build, or you might be able to get one of your "other" basses neck shaved down to a more comfortable profile as well.
I hope this helps in some way and good luck with the hunt.
