How do you know that Brinna is a Halfling? I didn't find any info on her? We even don't know if hirelings will be romanceable. But if she was a Halfling, then I'd pass on her, too.
The head used is recognisably one that's only available in EA for female halflings, so it's a reasonable bet that's what Brinna is.
And it's of course absolutely fine for people to find or not find any of the companions or hirelings attractive and to say so, but as with any other point made here let's recognise when we've made our preference clear and not bang on about it. I feel there's a risk here of Too Much Information being shared about personal sexual predilections and aversions and I think most of us probably just don't want to know quite so much about what our fellow forum members find attractive or otherwise in real life!
"You may call it 'nonsense' if you like, but I've heard nonsense, compared with which that would be as sensible as a dictionary!"