Emily,

Since I know the frame you are building I doubt if you are going to notice any squirreliness with it. So my recommendation is to go with the appropriate size handlebars but go with short reach. If you have Terry handlebars they are not short reach. If you do notice this squirreliness, which I doubt you will, then try wider bars.

Salsa and Deda make short reach handlebars.

I have the Deda 4 girls and love them.

Kathi