My DD(10) was 9 on our last trip. Even though she has been to WDW every year since she was 2, she still loves the rides like Pooh, Peter Pan, Small World Etc. She would not be pleased if we skipped them. She is particular about thrill rides- she likes 7DMT and Space Mountain, is not big on Splash at WDW (likes it at DL), and hates BTMRR. She has always been a character nut and even though she is older still wants to meet a lot of them-- although not ALL of them like she wanted on trips when she was younger. She "knows" about them- but it doesn't matter to her- she still wants to meet them, hug them, get pictures with them etc. So, I would say that it really depends on your girls. Having never been before, they may want to experience everything. I have seen plenty of kids that have a first trip at age 9 or 10 (or heck even adults) go nuts about the Pooh ride or Small World etc. Those rides are just special and designed so all ages will love them. I would plan on doing as much of everything as you can fit in. Being a first trip for them- they likely will be excited by all of it. My DD still loves character meals. As far as the pool, in November it may or may not be warm enough to swim- the weather is unpredictable- especially if you are later in November. We don't take the time out of the parks to swim every day-- we might hit the pool once or twice in an 8 day trip. DD likes to have some swim time- especially if we are at YC/BC, but the parks are far more important.
As far as EPCOT, it has been DD's absolute favorite park other than MK since she was 2 years old. It is a 2 day park for her. At age 9, they will probably absolutely love the Agent P missions throughout WS, especially if they are Phineas and Ferb fans, but even if they are not. DH likes those about as much as DD does-- I have had to make him give her back the communicator. At EPCOT, DD loves Soarin, Test Track, Club Cool, Figment, Nemo, Turtle Talk with Crush, the Aquariums, Mission Space, Living with the Land, the boat ride inside Mexico, wandering through and shopping in WS, Pick a Pearl in Japan, the performers throughout WS, and even the movies about the different countries (she likes seeing the other cultures). In WS at EPCOT, you can buy them passports and they can get them stamped at the Kidcot stations in each country- she has done that a couple of times, so she is done with that- but for a kid that age that has not done it, I would think it would be fun. The person at the KidCot station is someone from that country- and DD always enjoyed talking to them and maybe learning a word or two in their language. She also does still love meeting all the characters throughout EPCOT. Her favorite meal in all of WDW other than Princess meals is Biergarten- and she calls it a tie with Princess meals. She loves the German Band and the show they put on during the meal. If I told DD we were going to WDW and not going to EPCOT, there would be tears. If I told her we were going to WDW and not going to AK, she could care less--- not saying you should skip that one- DD has just never been a big fan. When DD was 7 and 8, she really enjoyed getting the Wilderness Explorer book and doing those tasks around AK and your nieces might really enjoy that-- after she had finished the book (it took 2 trips) she was back to not caring about AK. Personally, I like AK. She just prefers rides and princesses--- and she hates Dinosaur and doesn't really like Triceratops Spin (although she loves Dumbo and Aladdin- so I don't quite get that one).
I would say even though it is their first trip, I wouldn't book BBB for either of them unless they said it was something they really wanted to do. The girls in there are typically younger. DD's last time was age 7- and although she still loved Princesses (unlike a lot of her friends), she was the oldest girl in there at the time and felt a little too old for it.
Your nieces might really enjoy pin trading- if you want to spend the money for that. DD is all about that right now. If you want to try that, I would suggest trying to buy pins ahead of time, instead of waiting until you get there. You can find authentic pins for cheaper than you will find them at WDW. If you have a Disney outlet near you, they sometimes get pin booster packs in for cheaper prices. You also can find reputable pin sellers online or on ebay-- but there are a lot of people that sell cheap scrappers so you have to watch out for that. There are a bunch of threads you will find on the dis about that if you are interested.
