Since you are going on a Wed, my estimation is that either plan will be ok.
One point to consider is that in plan 2, since you are leaving it for the latter part of the day, you have no margin for error. So if you missed it, there will not be a chance for you to do latter show.
If you do plan 1, make sure you are in Shamu stadium waaaaaay in advance if the show is full, then you missed the train.