What's reasonable for spending time or not down there is a matter of personal opinion, one's budget, what one is accustomed to living, and how large of people you are!
Go to your local dealer and get aboard used brokered models to try out for yourself. No commitment to buy there if you do.
You will find out right away, or the Admiral will, what is acceptable or not.
As far as A/C reverse cycle (heat) goes, factory options on at least the Sailfish don't know about the Islander, however, for about $3K, either can be retrofitted with same.
Since both model cabins are not "spacious" as living spaces, I bet which one will be picked. Just make sure you don't enter the cabin of a 33 express! Keep the Admiral as far away as possible !