Thanks for the advice! My girls were eager to pick colors for their magic bands tonight (as soon as they found out we booked a stay they wanted to do that). They are also making lists of Must Do rides, activities, restaurants. With only 4 park days and no hopper ticket, we may have a hard time figuring out which parks to do. We all agree that Hollywood Studios was our least favorite park. A couple of fun rides and attractions, but not really enough to fill a whole day. DH thinks we should do 2 days at Animal Kingdom (we only did one day there last time and it was super hot, so we didn't have the motivation to do a whole lot there). The girls really loved Magic Kingdom though. They will be 10 and 12 when we go and the youngest is still very much into princesses, magic, etc. If you only had 4 days, which parks would you do?
That is a tough call!

If there is 1 park to miss, even with the new TSL, I would agree that we would miss DHS. We'll be going in December and even though TSL is now open, we haven't planned a full day there so that's the one I would skip.
Now, how would I spend the other 4 days? What do your girls like to do? At ages 10 and 12, are they rides focused? Enjoy shows? Like to do the extra things like hands on activities, scavenger hunts, etc?
My DD is 9 and we visit WDW at least once a year and I will say over the past couple of years she has added more input into our trips and it's been wonderful! I used to be a ride, show, ride, show, ride, character meet, parade, etc kinda person. I've learned from her to slow us down a bit and it's wonderful. We now take time to do things like the Wilderness stations at AK, Pirates Adventure in the Magic Kingdom and a scavenger hunt or similar at Epcot.
Now, for days in parks. We would do 1 day in the AK. Even with doing a number of the Wilderness Stations, with the longer park hours we find 1 day to be enough for us.
Dividing the other 3 days is tough as we could easily spend 2 days each in both the MK and Epcot. If it were me I would probably say 2 days in the MK to try and do as much as possible but my DD would disagree and spend 2 days at Epcot as it's her favourite park.
LOL - I'm not sure I've helped much at all!

Hope you can make something of this mess!
I will say, something I decided to do this trip as a surprise for my DD, now that she's getting a bit older is a tour. I've booked a 'Caring for Giants' 1 hour tour on our Animal Kingdom day which is a behind the scenes with the elephants. I've heard good things about this tour and figured it was a nice intro one. It also doesn't take up too much time at 1 hour in length and is just $30 a person. I think this will be a fun little surprise for her!
Happy planning!