Are you staying at the Polynesian? If not, I would cancel the Ohana that morning and try to get a PPO at Tusker House. That or lunch at Tusker House since you'll be at AK that day. Unless you really want to keep the Ohana.
The other thing I am wondering about is whether you are planning two Epcot days? Both Garden Grill and Bon Voyage are Epcot (or Epcot area) dining. If you aren't planning on two Epcot days, I'd change one of those to match whatever park you're visiting that day. Unless you are staying at an Epcot resort, though. At an Epcot resort, an early Bon Voyage breakfast could work before going to a park, especially if it's Epcot.
I'd also think about making one or two character meals lunch, especially if you are visiting at a very busy time. On busy days, QS locations for lunch can be a nightmare: it takes the "quick" right out of "quick service"! Even if you're not visiting at a busy time, we prefer lunch to breakfast (at most places, anyway; Crystal Palace is the one place we love breakfast). We find after a few hours in the park, we're ready for a little break, and a character meal is long enough it gives us a chance to rest and recover a bit before heading back out.
I don't think it sounds like you've planned too many character meals, but it's really a personal decision. My family loves character meals. Sometimes we do two a day the entire 5 or 6 days we're at WDW.
6 PM is also a late dinner for my family. We sometimes have no choice, though, when it's the only reservation available! We make it work by having a mid-afternoon snack and a rest at our hotel. My family goes on
Disney vacations knowing that our Disney vacations are not for sleep! We are early risers in the first place so maybe that helps us out with waking up at 5 AM while we're, yes, on vacation (it feels early even to us, though, due to the time change). Even with a "late" dinner, we try to make it to bed no later than 10 PM (I've found this is very do-able even when we're staying at Pop). We don't watch fireworks from the parks. Sometimes we stay in a theme park view room at the CR so we can watch fireworks as we're heading to bed, though.