We were there last week and have stayed there every year for the past 6 years. We always get a lower level pool view room. The pool view is very nice since the upgrade. We were upgraded to a higher level room last year in the Frontier Tower, and could see DTD and DL as well as the pool from our higher window. That was nice, but I would have preferred the Fantasy Tower with the lower level room.
We surprisingly have never been in the Adventure Tower. We have only been in the Fantasy and Frontier towers. We prefer the Fantasy Tower, it is the building with the lobby and shops, and also a closer walk to DTD and the parks than the Frontier Tower. Those extra steps are a pain when you have been in the parks from open to close. Also Goofy shows up in the lobby there quite a bit and it is fun to accidentally run into him when you are coming and going to your room. We don't care for Frontier because it is farther, but depending on what you like, it is fine too. Frontier Tower is right by the Trader Sam's bar which is a fun place and also right by a pool entrance. That part of it is nice, but it would still be our 3rd choice because it is farther from the shops and a longer walk. Adventure Tower is between the other 2 towers. It would be a good choice as well because it is right next to the building with the lobby and shops, not far from Trader Sam's and still a shorter walk to DTD/parks than Frontier. Really even if you get stuck in the Frontier it will be great. The rooms are fabulous, the lower pool views are great, and the resort is great.
I don't think they will put you in a DTD view room if you ask when you didn't pay for that category. They might upgrade you, but I don't think it is likely. When we arrived this year, we specifically requested not to be in the Frontier Tower if at all possible. We were there in the morning and our room was not ready, so they easily accommodated us. When your room is not ready, they give you your keys and then they text or call you later to give you your room number. I'm pretty sure had we not made the request, we would have been in Frontier, because when they called us, they told us that we needed to come back to the desk to get new keys as ours would not work for the room they put us in. I would bet that if you are arriving early they will try to put you in the tower you request; however, if you are there later at night when most of the rooms have already been assigned and are occupied your chances of getting a change if you are in a Tower you do not want are not that good.
Have a great trip! All the 60th anniversary stuff is terrific. I almost cried when I saw the castle all fancied up in person. The Paint the Night parade is the best parade I have ever seen at a Disney park!!! If you can do the later parade, it is a whole lot easier to get a spot on Main Street with less wait. The new fireworks are fabulous!!! We saw them from the Blue Bayou Fantasmic Dining package area and loved it. The special effects in that area were great. We were going to see them again to get the Main Street special effects experience the next night, but they were cancelled.