If you swaddle or use the miracle blanket, what does your LO wear under/as a base?

DD is 8 weeks old. Her room is usually around 71/72 degrees and I have the ceiling fan running on low. I usually put DD in a tshirt or long sleeve onesie + socks. When I get her up in the morning her temp seems average or slightly cool. Everything I've read about SIDS says not to have babies overheat, so I'm afraid to put more on her. What do you think?