Most of the bubble tea shops I've seen in the U.S. were "to go" places. The few with actual retail space and seating were not too impressive in my opinion (Mozart said the same thing in this and another post). They were so plain that you could change the signs and menus and open a sub shop in the same space the next week. The bar for decorating is set pretty low!
The busiest one I've seen was actually the ugliest. An old warehouse with exposed wiring and little more than a long stainless steel bar and second-hand barstools - in fact, I think it was previously a daiquiri bar. But it was surrounded by nightclubs within walking distance of a major university, so it became a huge "between classes" and "after clubs" meeting place, as well as a place for non-drinkers and underage students to hang-out. Location and uniqueness (i.e., no competition) had the place packed.
I've seen two shops that appeared to have really worked to create an atmosphere:
1) an Asian theme featuring bright lights and vivid colors, lively techno music, lightweight and easy to move tables and chairs, and lots of that inexpensive stuff you'd find in Chinatown hanging on the walls and from the ceiling (including one of those huge dragons you see in cultural celebrations). This place was on a retail street between a campus main gate and off-campus housing, and on the same block as a pizza joint, health food store, hair salon, used bookstore, tat parlor, and some quirky boutiques. Lots of foot traffic.
2) a performing arts theme featuring a deco look, track lighting, soundtrack and local artist music, and bistro style seating with theater posters and memorabilia. This place also served coffee, hot chocolate, salads/sandwiches at lunch and desserts at night. It was in the theater district next door to a large parking building. It drew a lot of artistic types in the day and a very upscale theater crowd at night.
The more I think about it, decor just doesn't seem to be a major factor in the success or failure of the shops I've seen. Location, product quality, and service are what seem to really matter. New shops almost always get reviewed by local newspapers and college publications, and reports of rudeness or bad service can be deadly. Any decor that allows the clientele you want to congregate and feel at ease in your store will probably work -- so long as the design doesn't take away money that would be better spent on something else, and so long as the layout you create facilitates good service and an enjoyable experience.
I hope this was in some way helpful. I'd really like to see this happen for you!
