Sivard won an account with Dragon King. Congratulations!
In response to the questions:
Here's a general weapon tier:
LB3 Event SSR (assault) > LB3 Event SSR (defender) > LB2 Event SSR (assault) > LB3 Event SR (assault) = LB3 Disaster SR (assault) > LB1 Event SSR (assault)
Attack + Burst damage bonus is generally weaker than other options. A combination of character attack + HP and elemental attack is often ideal.
An SSR Gatcha eidolon isn't better than an event SSR eidolon as a primary eidolon until LB2, generally. You can simulate specific situations using my Constant effects calculator.
Save your draconic eyes for SSR kamihime awakening.