"I have the biggest house out of everyone I'm afraid. They did say they can't wait till next year as it was so nice!!"
"That's guest's for you"
This is the problem, you all need to stop thinking if it, as you "are hosting" and think of it as "all of you as a family are deciding what to do for Christmas dinner"
We all go to my eldest DD's (sometimes my Mums), because they have the biggest houses. We all construct the shopping lists, decide who gets what and pitch in on the day. I do less whilst there, usually because I have my Mums house/tree etc to do (I am her carer), but this year I had to put up my DD's decorations as well (ongoing work crisis).
You are not hosting, IMO, if it's family coming, on a family occasion, IYSWIM, rather than privately arranging a dinner party and inviting people.
Start the conversations about you needing others to help, straight away and re-negotiate during the year, if ithers object, you don't have it at yours, it is simple.