I am surprised no one mentioned this but will there be any support for potion recipes? There can be various conflicts with brewing when it comes to using a single ingredient. For example, the ender pearl and eye of ender are very popular ingredients for teleportation related potions.
I feel that adding this feature could prevent such issues as most mod makers barely deviate from the usual awkward potion base.

This is a little trickier than I thought at first glance. The main issue is that brewing recipes don't operate like any of the other recipes. It doesn't even really use the recipe system at all. For instance, all of the vanilla potion brewing could be considered just a single recipe with multiple possible inputs and outputs. This makes it difficult to integrate with the concept of recipe conflicts. It might still be possible, but I'm going to have to workship this a bit.