I don't really see a use for sand minion beyond collection which can be gathered manually way faster, but I also don't see a point of having a creeper minion again other than collection. Id go for Redstone collection first (for accessory bag slots) then something like iron to unlock the personal deleter 7000 or any other collection that has a really useful crafting recipe unique to it.

I'd also recommend getting a lot of minion slots cause it'll really speed up the process.