Why doesn't your server just run both? they are both very good mods and compliment each other very well, as you say you don't really know what the builder and fillers do i suggest you play around with them, i think you'd be impressed.
Adding a bunch of rainbow ores with no use (except maybe make a shovel) is what 12 year olds do with their mods. She's obviously planning on adding more, but right now it looks like an infantile attempt to do everything that's going nowhere.
There is only one ore which has no use currently (tungsten), all the rest do. If you read up on Eloraams history before minecraft mods you'd discover that she has a seriously impressive history in relation to programming and just general creativity, so i wouldn't be so quick to judge the fruits of her future output.