perhaps you guys are just severely underestimating electivire?
on the top 20, vaporeon, starmie, suicune, gengar, zapdos, and blissey usually carry an electric attack. You might see the odd twave celebi or tpunch metagross as well.
This pretty much means electivire has 6-8 pokemon in the top 20 to get a free switch in and boost his speed as well. from the top 20 pokemon, a moveset of tbolt / flamethrower / cross chop or EQ / hp ice or hp grass + that speed boost will:
beat scizor
beat heatran with eq, might win with cross chop depending on item and what heatran does
beat salamence
beat tyranitar with cc (wont do it with eq)
beat zapdos most of the time unless its a very bulky calm zapdos
beat blissey with cc
beat gyarados with tbolt
beat lucario
beat infernape most of the time with eq
beat gengar with thunderbolt and if gengar is scarfed, you get to see a pokemon for free and then attack from there
2hko metagross with flamethrower but he might ohko with eq so try to get him on switch
beat swampert with hp grass
beat bronzong most of the time
usually wont beat azelf because it will probably just explode
might lose to celebi because ft wont 2hko most of the time and gk 2hkos
beat vaporeon
beat shaymin-s
beat starmie
beat skarmory
beat suicune
so i would say that 18/20 pokemon in the top 20 would lose to an electivire like that easily if it got his speed boost
and for items, life orb is pretty good but i personally like shuca berry for weak earthquakes, i also like running expert belt as well.