Remember you CAN pool hop at Uni Resorts.
Take a good look at some of the other areas, like Disney they have many family rides outside of the Suessland and Popeye area. There are some great water rides and even if you are soaked you are just a very, very quick boat ride back to the resort. Simpsons has a new family twirl ride that is very appropriate for kids and their new food area there is perfect for young family tastes. The area isn't going to scream of the Simpson TV show especially if they are unaware of the Simpsons to start with. I'd had off the kids for a minute and check it out if you are uncomfortable, just to make sure it is ok for the kiddos but I bet most of it will be fine.
When small my kids loved the Pteranodo Flyers, 36" tall minimum and the older one would likely love Dudley.
6 days at the Royal Pacific is a long time. That's 6 days of essentially unlimited Fast Passes!
It's not going to be like any WDW vacation you've ever had.
Relax. Take it easy. Sleep in. Go back to the room and relax poolside during the warmest part of the day. Check out the other 2 resorts.
With Universal's Express Pass and that many days, you'll have plenty of time to do everything.
Only 2 attractions are not covered by Express Pass:
- Harry Potter and the Forbidden Journey (FJ) - 48" height restriction
- Jurassic Park's Pteranodon Flyers (PF) - maximum height 56" unless with a child
Both these should max out at about a 1 hour wait. If you don't want to wait, go for early admission one morning (WWOHP opens 1 hour early for onsite guests), head to the wand show at Ollivander's (this is the longest, slowest line; the show's not particularly worth the wait unless you are a HP fan), ride FJ, and then head over to JP (which is next to WWOHP) to ride PF.
You can get
soaked on Uni's 3 water rides: Jurassic Park River Adventure, Dudley Do-right's RipSaw Falls, and Popeye and Bluto Bilage Rat Barges. For the River Adventure, a snug poncho should be enough to keep most of the water off (watch the shoes; tuck them up under the seat in front of you). However, the last 2 rides you could get head-to-toe drenched. We either bring swim suits that we change into or do both back-to-back and then immediately head back to the room.
Uni is weakest with fast food at the parks. Pretty bland burgers, pizza, and chicken strips. (It's like WDW used to be about 20 years ago.) However, Uni's Table Service (TS) options are good and cost about the same as most typical chain restaurants. In my opinion, all the TS options inside the parks are good. Mythos is legendary for inside a theme park; very nice if you want a classy meal at a reasonable price.
Most Uni restaurants take walk-ups on short notice although I tend to make a reservation at the kiosks near the entrances of the 2 parks (you'll walk by them after you enter the parks) after I arrive just in case. Typically, it saves a few minutes of waiting for a table. You also can make a reservation at the hotel. Generally, Uni is not like Disney, which has gone ADR crazy.
Also consider the Hard Rock and Jimmy Buffet's Margaritaville out in CityWalk. Both are fun for kids.