You will have very little trouble making PS (DL version of ADR). One of the perks of a DL vacation is not having to get up at the break of dawn, using an atomic clock to make sure you get the ressies that you want.
Everything will be open. It's good to make PS during busy times though.
What day and when is up to you. I like using packages like the WOC during busy nights. I bet everyday of your trip is going to be busy though, so which day for WOC is up to you. I like saving a big night time event for the final night. It's a good way to end your trip. Maybe Friday ngiht for Ariels. We prefer to use the package for the first show and make our PS during in that window. The CM can give you the restaurant times for the first show.
I like Blue Bayou for lunch. I get the first reservation time of the day, usually around 11:30. This way I can request a waterside table and have little to no wait. I think having a waterside table is very important, but that's just my opinion. Half of the dining experience is being close to where the boats cruise by in Pirates.
I've never been to WCT. I've seen mixed reviews. I'm sure another poster will share their experience.
Napa Rose offers seats at the Chef's Counter. If you are interested in that experience, ask for a Chef Counter seating. I think there is two seatings per night.
I would recommend Storyteller's Cafe. It's in GCH and has a character breakfast. One of the nice things about Storytellers is that you can order off the menu or get the buffet.
If you are thinking of a character breakfast I recommend Minnie's Breakfast at the Plaza Inn. The buffet is fine, but the best reason for going is the character interaction. It's the best of any character meals my family has experienced. We usually see 10-12 different characters at our table and they all don't rush. We have had some incredible experiences in this restaurant. I highly recommend it. The restaurant reminds me of Crystal Palace and is located in the hub, but to the right of Main Street.