You only really get 'proper' bus stations in the British sense in towns where there is no rail station.
Or where the bus station is the other side of town from the train station with few if any buses serving the train station (e.g. Halifax, Keighley). In Keighley most of the buses which do serve the stop outside the train station come from the same places as the trains...
Halifax is a fine example of a nice idea poorly executed. They've tried to build the bus station round a listed building and ended up with a bus station that lets in rain and wind.
I thought the new bus station in Slough had to be an improvement on the old one until I visited it and found that though it's no longer dark and dingy you now get rained on when you're inside.
Mansfields current bus station is ugly, although why it is built in a car park is odd...
The new one loooks good, it will have a walkway to the train station, you can see it going to the station in the pic below
The current bus station was built in the early 70s. They knocked down the church my parents got married in (in '72) to build it. Hasn't lasted long.