Hey, I wanted to suggest AgriCraft since it is an awesome Mod. For those who dont know what it is: It adds new Crops (Like Mana Petal Crops) which you need to get trough Crossbreeding different Crops, and you can make them stronger trough breeding them with themselves. Sorry if it isnt clear enough, here is a better explanation: http://www.curse.com/mc-mods/minecraft/225635-agricraft It seems like you could make a really fun Questline for this aswell.
I'm all about breeding things; loved breeding bees and trees back in the day before it got nerfed into worthlessness. Still, mod seems to have an incorrect philosophy, if it thinks inbreeding makes things stronger; just look at hillbillies, not exactly the best and brightest. That having been said, and having read the mod page linked, I am all for this being implemented, as it'd finally give me something worthwhile to invest my time in, possibly offering tailored crops and plants to the community on demand. As I recall, I was the one who bred the fuel saplings back in the day.
We haven't nerfed anything about bees or trees in this version, try it out! As for Agricraft, it's a cool mod that we were considering. We'll see what we can do