[Chyuu]

I currently have a lvl 28 assist going AoE and I have a few questions:

With stats:
Do I necessarily have to have Str?
If I wanted to use Bgvur Tialbold later on, when should I cap my Sta and start adding int?
If not, should I cap Sta?

With skills:
Is Burst Crack really better that Piercing Serpent?
Does Asal use MP, FP, or both?

I currently have my points all on Sta and have just used my reskill to set up for my AoEing.