Unsure if these might be out of scope of the mod, but:

1. A config option to let Biomes O Plenty flowers/plants be plantable on other kinds of blocks; example use cases would be Contenttweaker blocks or Underground Biomes blocks. Currently, they are only plantable on BOP's and vanilla's grasses.

2. A config option to cosmetically change the display coordinates of a certain dimension. An example use case for this would be with dimension stacking: if you put the nether under the overworld, the overworld's lowest Y coordinate would be 0, and then traveling into the nether would put you at Y=256; with this config option Y=256 would become Y=-1; Y=255 becomes Y=-2, and so on. Conversely, a dimension above the overworld would have its Y=0 become Y=257, Y=1 becomes Y=258, etc. This would purely be a numerical change in scale, no actual alteration to dimension height or anything like that.