1) increase free company chest slots by 1,2 or 3 slots depending on housing size.
2) add internal summoning bell, market board, and the book that allows you to view cut scenes which is available in the Inn rooms.
3) add weather effects to the zone just like it does in their respective zones.... example thunder storms and raining in the shrouds.
4) allow more items to be used as both indoor or outdoor. ( hot tubs, chairs and the gargoyle statues are just a few small examples )
5) give a permanent buff towards exp or item drops or such scaled accordingly to the size of the free company house.
6) more allowance space for more items to be placed inside the house for large houses.
7) I know that there are a large group including me who would be able to rotate in which way the house sits on the plot so that your front of the house could be facing a different area of the plot.