A cot without good insulation can be brutal. I have an insulated air mattress and put a piece of ensolite on top of that. I've slept warm down to 5 with it so far.
Do you have trouble with condensation under your sleeping bag?
I do, maybe my setup is wrong when using a cot. I put down a thin closed cell pad, on top of that a foam “egg crate” pad 3” thick and down bag on top of that. The bottom of my sleeping bag gets quite wet. Solution?
