My macbook would do something similar. It didn't get as hot, but if I left the wrong program open (Outlook), the battery would be around 5% when I took it out of the bag. If I made sure to close everything, sleep was pretty efficient. That was many years ago, maybe things got better.

There is a setting on Macs to allow the laptop to wake-up sporadically to update opened apps during sleep. You can totally disable that.