Blue or Silver, in my opinion Silver's the better rival, although this is mainly based on the pokemon he has (Sneasel, Gengar, Alakazam and Magneton) I love Dark, Ghost, Psychic and Steel types so yeah Silver wins on quick pick but comparing is different I think that Blue would win just because he has a team that could destroy Silvers, just listing what pokemon he would use.
Sneasel - Charizard, Flareon or Arcanine (based on game and choice)
Gengar - Alakazam
Magneton - same as Sneasel and Rhydon
Starter - Opposite starter, Gyarados, Arcanine or Exeggutor
Crobat - Rhydon
That's all I can think but, obviously there are advantages Silver can take but I think Blue has more.