I thought it would be interesting to document people's thoughts on this. Long ago I decided that I did not have the time to play over games by all the top GMs. The practical thing to do was pick someone near the top and aim to play over and analyse his or her published games. For the obvious reason plus some opening repertoire snaps I picked Michael Adams. I don't just play over his wins either. But there is a nice win v World Champion Vishy in the last New In Chess.
I have tried playing over some Carlsen games from time to time but find him too complex.He wins equal endings!
And finally I try to follow Tukmakov's and many others' advice and "Study the classics", where often ideas are found in purer form as defence is generally worse than by top GMs today. I recommend his modern Chess Preparation book.
How about others?