I agree that there are lots of similar sounds, although I never really see Underworld as working on just one thing at a time.
River runs are probably made up from work the was started 15 years ago, and inspiration from other projects they are doing currently. It probably gives some direction in how they want to move forward..
There are so many songs that have similar elements to them, im sure it could take ages to list them all - thats why i have got so lost on the gigography
