Thank you! It's been really fun grabbing what I like from other sites, adapting it to make it my own, and hopefully building something useful for the folks on the forum.
Soundings have already been added. When a model that currently supports it (HRRR, GFS, ECMWF) is selected you should see a 'Sounding' button along the top bar. Click that, then any place on the map and a sounding will generate.
I might try and change that flow so you don't need to click the sounding button at all and can just click anywhere to generate it but for now that's how it goes.