Everyone has different tastes of course… but I won't even visit a scary horror town. I know a lot of people are impressed with Aika, but I just don't like scary/icky stuff.
I know a lot of people like strong themes with "clever ideas"… but I mostly keep going back to a dream town if it's very well designed and pleasing looking. Ones where there is a very beautiful use of trees, bushes, paths and flowers and peps.
Some examples where I find the exteriors to be particularly well designed and beautiful:
North (7900-3285-6095), Chibiton 4600-2805-3661, さにれに 3400 - 0431 - 3656, Royall - 6500 - 3304 - 9459 , Cit?lune - 4800-2245-2005, Lilane 6400-2587-0340, Shamrock 7500 2364 9142
I also like towns with clever use of interior furniture, etc, to create a neat themed room. Shamrock 7500 2364 9142 and Spa Town 3900-0129-0481 has a lot of really neat houses for example.
I've seen some towns with very creative themes, like trying to theme the whole town after a particular movie or series of movies… and I visit them and think, "yes, that's clever"… but if it's not actually really well designed throughout the town I find myself feeling disappointed at the lack of follow through or the lost potential of what could have been "really cool". So more often I guess I like the towns with a more general theme (like North) which is done very well than a really clever theme (movie town) which is not fully realized.
So a "blue town" or a "pale" which is very well done I would probably like a lot.
I like it when there is things arranged around PWPs in a pleasing way like bushes, trees or flowers. When people think about creating a garden that looks like a garden a town would have with thoughtfully placed bushes, etc…
I like it when the PWPs and gardens, etc, are placed in ways that takes a natural advantage of the landscape of their town, like putting something near a beach cliff because it fits the theme and is pretty… or near a waterfall, etc.
Like some others have said I love it when the season of year, the time of day, and the weather is all paid attention to if possible when the dream is created. Like Citalune being in winter is perfect. It's not always possible or reasonable to do this and it can be fun to visit a town at different times of day and seasons and see how they updated it for those seasons, too. But it's nice when it's done consciously.
on the exterior of the town, when people just kinda place QR tiles wherever because they fit a theme or have their favorite character on them… but they don't match the other QR tiles or how the town looks overall? I find that kinda garish.
Also if the paths are not well placed and I find myself not able to get where I want to go organically because paths are poorly placed and trees and bushes block my way, etc, I get frustrated.
All the flowers don't have to be the same color, but I like when a color scheme is thought of at least in some areas. Like one area can have blue, purple and white flowers… another could have pink and yellow flowers. But sometimes people put flower colors which are too contrasting or garish next to each other or just kinda willy nilly and I don't care for it. Sugardew 6400-3072-1629 is a good example of one that has many colors and species of of flowers mixed but they are thoughtfully placed so that they look pretty together. North (7900-3285-6095, white, purple and blue) and Royall - 6500 - 3304 - 9459 (pink and white) are more limited in color palette, but also very beautiful. I guess I mean, think about how the colors go together.
Like some others have said, I like towns with some cozy places to sit or a little code grove of trees with a PWP. When most of the town is just QR path code, no grass still showing… or there aren't very many trees, I find myself turned off.
If the exterior of the town (paths, pwps, tree,s flowers, etc…) is not well designed, I seldom take the time to even visit the inside of the houses unless someone specifically said they were cool.
If I do make it inside the houses, I like seeing the furniture used in interesting or beautiful ways, not just a whole set of matched furniture with nothing else. I wish I was more clever with this myself, but I know when I visit dream towns with particularly nice houses, I'm always impressed by someone who mixes different furniture sets in a beautiful way or has things customized in a good way.
I don't typically visit the inside of villager houses or the museum unless I'm interested in a particular thing. In fact if I go in one of the larger resident/mayor houses and am not impressed I won't visit any of the other ones.