I know Jorb and Loftar haven't finished with the personal beliefs system (Or so they say) and I am pretty happy with it so far, but I did read somewhere some people thinking of rewards of some sort, like a bigger bonus at the end of the slider rather than just a normal gain like 1 to 2.
What if when you reach the end there is a way you can specialise, at full nature you could have perks that improve crop quality or animal quality. Smithing/mining for industry, and similar things for all the others, death gives you increased stats when low on HHP, and day could improve stamina during the day or even faster health recovery. Maybe with no negative sides as well, but I'm not too fussed on that.
Of course you wouldn't be able to have both perks, a choice that locks out the other? And you need to put several 'changes' into it before you can actually use it.