I just want interesting rallies and games. It's hard to say what match is going to be interesting. For example I generally hate Roddick against Federer matches because usually Roddick can't hurt Federer. It's usually the same old thing, Federer blocks the Roddick serve back and outrallies him from the baseline. Yet Roddick almost defeated Federer at Wimbledon this year in a pretty decent match.
Miloslav Mecir was always interesting to me if he played a baseliner like Connors or a serve and volleyer like McEnroe.
Laver and Rosewall were all court players who could run like lightning so their rallies and angles were pretty stunning.
Of course Sampras and Agassi which is an all courter/Serve and volleyer in Sampras versus a great baseliner and super returner in Agassi.
And the recent great match up in Nadal-Federer. Both great baseliners who can run like the wind. Nadal with the much heavier topspin and better overall consistency and Federer with the greater offensive forehand (note I write greater offensive forehand. I don't know if Federer has a better overall forehand.) and great serve.
I liked this Becker-Sampras match. Fabulous match with two serve and volleyers.
And of course Borg-Connors, two baseliners who could do anything and were different types of baseliner.