I heavily dislike the SP mod. If you play with it and don't do anything about the settings, your town will change job and partners every other day - and young males will often pair up with elderly females and thereby not produce any offspring, because these marriages are, of course, the ones that somehow last. It is a major hassle to go into every darn setting and make it the way you want to. And you can't be sure even then if it will work to your liking. Forget one little thing, and you have spend time setting things right again manually.
But it's also a major hassle to correct ages and fix those abominations that appear if I turn aging on and off. *plucks hair*