Which of these options best CE to level

For reference, I need a buster 50% starting charge CE to hold me over until we get that plug suit JP has that allows more busters to 3 turn without starting charge CEs.

I somehow have zero copies of BG despite MLB K scope, and fragment of 2030, 1500 MP, and 12 CE bombs.

My main two choices at this point are to:

1. use 5K MP on holy night supper and level that to 100, as it is 15% NP and 15% crit (I cant decide on the value of the crit at all since no impact on NP)

2. Save my MP and level 100 for the summer superb vistas, sublime artistry CE - 8% buster / arts and 10% NP.

When using Oberon my understanding is they should be quite similar on final NP damage.