If you can make Caches and exchange those for Orb Aggregates or can gather up the orbs yourself to craft the needed amount of them, I say craft it if it will get you the experience to move toward the next level. If you are just planning on purchasing them, I would just sell the formula and look toward another level three formula to complete that would not break the bank as much (it would cost you two million or more gold to purchase the needed Aggregates without using zOMG! to gather up orbs and help in the accumulating process).
Ah. If you can get your hands on a decently priced Formula 3: Levianovo, you can use that as your level three formula. I made four of them as one does not require much outside of ten of each Leviathan's Grace item and the five Jade and one Baroque Pearl it calls for.