I'm gradually getting the hang of this modding lark, as long as I don't have to do anything to do with graphics!!
This mod increases the maximum number of residents in both wooden and stone houses to 6

To maximise its usefulness, I've also reduced the minimum gap between pregnancies and increased the maximum childbearing age to 50 rather than the current 40.
I tried to expand the residence dialogue box so you didn't have to scroll, but every time I played with those parameters the game crashed horribly, so I've given up for now!
Have fun and let me know if you find any problems

Edit - tweaked slightly for better balance! Max childbearing age is now 45 and I've slightly increased the minimum gap between pregnancies (but still lower than in the vanilla game).