Small vs medium sweater

I’m knitting a sweater size small. I think the overall length 19 1/2” may be problematic as the person is tall 5’6. The finished bust is ideal in small. Here’s the issue
Bottom to sleeve shaping
Small 8-1/2. Vs Medium 10”
Bottom to neck
Small. 17-1/2. Vs Medium 19”
Plus 1/2 for shoulders.
I though I would add a border to bottom of sweater using a H CROCHET hook. Two rows one single crochet and one row of crab stitch.

Welcome to KnittingHelp!
The easiest place to lengthen the sweater is from the bottom to the underarm. You can lengthen or shorten here. It’s a nice idea to add the crochet hem too.