I think I'd go for the just below the sill.

Can you hang the drapes any higher so you don’t have to hem them?

d say leave them as long as possible.

They are already higher than the window. I think the main issue is that my son doesn’t want to take down the rods, patch the holes, sand and repaint the walls, and reinstall traverse rods that will probably be replaced eventually. Quick fix is to have Mom hem the drapes! 😊

Can you hem them up without cutting them? They sound a bit formal, so I would keep them longer. Lightweight curtains are nice below the sill.

Are the baseboard heaters electric or hot water? If they are electric, the curtains must not touch the baseboard heater, but if they're hot water they aren't usually an issue as long as the curtain is not blocking the baseboard preventing heat from coming into the room.

You can just put a loose knot in each one, to kind of hold them up and back, assuming they don't need to traverse and actually be super useful. Daughter keeps hers knotted like that, and it's cute. Are there shades or blinds on the window as well?

Heaters are hot water but the curtains cover them and block the heat. Curtains are drawn at night, as they are the only window treatments. The hemming will probably be a solution for a year or two at best. Just not sure whether to do sill length or “high water pants”

My drapes hang in front of my bedroom hot water heaters and I still get heat. Please do no tie real drapes in a knot that always looks like a dorm room IMO. I would try to hem them if you must folded up but not cut to for now just to clear the heaters, Once all the furniture is in it won’t be very noticable and does the job for now.

Any chance adding a shade is an option? I did a simple roller shade in my daughters room then added trim to customize, like this

Leave them alone. The heat still comes into the room. and plenty of it. If you MUST worry? Get some curtain hold backs, liift them that way. The more curtain you lift over the tie at leading edge? The more heat run uncovered.