Chossid:
You’re making (at least) two big mistakes.
1) If someone will sleep, it’s a chiyuv to do so in the sukkah.
The Lubavicher “minhag” is to sleep outside of the sukkah.
2) The R’ma is specifically talking about when/where it’s cold, or married men.
Lubavicher bochurim sleep in the house even when it’s nice outside.