Because EVENTUALLY, you'll also want an on-element Grid for Wind. It might not be today, it might not be next month, but it will happen.
And when it does, that FLB Garuda Deva is amongst the best weapons to have. So, MLB it for the future. You can FLB it when the time comes to level it up. Again, remember to leave yourself with Silver (45) and Gold (25) drops to FLB it!Yes, more slvl = more points. If slvl1 SR gives 10% chance then slvl2 gives 20% chance. And slvl3 gives 30% and slvl4 gives 40%.
ALWAYS use SRs at slvl2, at least. That way you've spent 45 points for 70 points.
Slvl3 is 90 points spent for 105 points, and slvl4 is 135 points spent for 140 points. These two are optional, but still worth it when trying to speed up your Grids.