Not trying to push it, but you really need to read my review - it's full of very specific information about the cruise that can be very helpful.
I hear what you're saying about Celebrity - if you're an old fart like me, you will absolutely love them! But they are a bit sedate, so if you're younger and want more action, Celebrity or Holland America really aren't for you.
As for Ensenada, you really don't have to do anything in the port. You either take the transfers to or from the San Diego Airport and go or come right from the ship, so it's no big deal at all.
And I also hear you about the days at sea. While those one-way trips to/from the West Coast can have 5 days at sea, some people really enjoy those - great way to relax. I have a group going on the Celebrity Solstice where they're flying into Honolulu for a couple of days before the cruise around the Hawaiian islands, followed by 5 days at sea to the West Coast. They chose this over the 7-night Pride of America cruise because it's a MUCH nicer ship and the 11-night cruise is the same price. Just depends on what one is looking for, their budget, and their lifestyle.
But the bottom line is, cruising around Hawaii is AWESOME!!!