Wow, a max speed Eelektross with a choice scarf doesn't even reach 300 speed. That's pretty bad.
Edit: Oh, that was adamant. My bad. 327 with a scarf. Still bad, just one point under base 100 speed, and your rarely see pokemon with 100 speed running offensive roles without a way to boost speed. There are also pokemon like Celebi that uses their bulk for offensive roles...that's more of bulky offense, though.
Even with the low Base Speed issue, Paralysis chances from Spark, Thunder, Thunderbolt, and Discharge, plus the guarantee from Zap Cannon or Thunder Wave, can help 'tross with outrunning something, aside from a Ground Type or Limber Ability Pokemon. Plus, Rock Tomb becomes an option for the sake of adding damage to your debuff Moves. Mixing is what 'tross does best in my mind, and that applies to added Move effects, too.
Ever see a Corsola 1-shot an Uber? Arceus bless Pokemon Stadium 2...
WARNING: Strong profanity and extreme hilarity in this video. Viewer discretion and pointing-and-laughing advised.