I don't have any bushes in my town yet because I'm not sure about how I want to lay them out, but I think hydrangeas are the prettiest! I've been stocking up on bushes since T.I.Y opened.
For color I like White Azaleas since it overall fits my town. For flowers I like the red hibiscus best, though that takes a little more effort to get since you have to rack up those island points and wait until they're available for sale on island. Even then I have to figure out what area in my town they'd look best in.
I love the White azalea, mostly because it really matches the paths I'm currently using, lol.
And they're really pretty regardless of the path situation.