It's a common practice in Middle Eastern music to keep songs together as sets ("wasla", "fasil") in the same key (rhythm and tempo would vary). In North Africa this can mean up to several hours.

Cape Breton fiddling often strings together tunes on the same tonal centre. Scottish fiddling used to group tunes by common key signature instead. Both work.

Too many changes sound fidgety. A planned sequence of changes can be very effective.