what to do

I have expanded all my land so is there any point holding on to mallets, stakes and deeds?

Well we don't know what the future update have for us on the other side of the river or above the cliff. If you don't need it now then sell them all or just keep them.

For now, u dont need them so i suggest trading them for barn/silo or food items or just sell them for max on roadside shop, they will be gone in seconds lol