Without question or hesitation, the Little Mermaid ride is top of my list. That is one of my all-time favorite Disney movies and soundtracks, and I think it, along with TSMM, will be among my favorite rides at DCA. I can see that the line for it will be ridiculously hideous, but if TSMM's line has managed to kind of become reasonable in under a year, hopefully the same will happen with the Little Mermaid ride too.
I am one of those kooky folks who actually likes Star Tours - still - but let me clarify that the reason is because I don't go on it often anymore. For a while, in the late '80s and early '90s, my friends and I rode it a lot, but then I was away from DLR for a few years and when I returned, we didn't go on it. I didn't have a chance to burn out on it too much like everyone else has. So basically, from 1995 up until 2008, I didn't ride Star Tours at all (all of my friends who used to ride it confessed that it made them ill). Finally, last year, one friend agreed to go on it and I made my grand return to Star Tours and still enjoyed it! So I will be happy with a new film replacing the old one, but I would still enjoy it even with the old film, just because I haven't had a chance to really get sick of it.
And about Carsland - I do not have kids and who questions the implementation of Carsland over, say, a Toyland or a Monsterland or a Nemoland or whatever (there are a few of us out there). I like the movie but it is not my favorite of the Pixar collection and it does not hold the same magic for me as some of the other movies. That said, I will keep an open mind and give it a chance. I always like it when DLR adds new lands (I am also one of those kooky people who loves ToonTown!) or rides of any kind because it breathes new life into the park(s) and provides additional places to search for Hidden Mickeys, eat, shop and soak in some of those fantastic Disney details we all love. So if nothing else, I may scoff at the idea of Carsland, but I will be there, looking for Hidden Mickeys and clever little nuances and details, and taking pictures.
I also HOPE that the possible reimagining of the People Mover with a WALL-E or Incredibles theme is something that comes to fruition. I think that would be fantastic!