Knowledge of boss patterns is also pretty vital, but that's something we nutaku players have an advantage of for being 1 year behind DMM version.
That said, as with event weapons I do recommend that players get as much orichalcum as they can, even if it's a bit of a tedious grind, considering how useful 4LB will be and how the end game is to have all elements working anyway.
As another note, 5 orichalcum per 2 weeks is more than enough to 4LB every single upcoming event weapon, or so I'd project for half a year given the event pools we get. The remaining orichalcum can be spent on 4LBing previous weapons, and then one would have excess that is completely pointless to them unless they whale/ get lucky with hime or dragon eye weapons. This basically means that to keep up with f2p content, one does not necessarily have to perfectly clear GO consistently, there's a small window of leniency even if your target is to keep up with all content.