Just a thought, but set her up with a cleaver and botrk and she passively harrasses the enemy tank just while csing. her counter gank is strong with q and e(massive movement speed boost and counter cc) start dorans ring and you basically cover your mana cost since shes such an amazing ccser(not ideal, but at least her q partially scales off ap)
not a thing. Sivir has 2 major weaknesses in top lane that would make her jungle food for days. One is no real escape. Pre-6 you kinda just run away but if they get you in a CC you done. Second is she is more of a utility ADC then one to do damage, so you would take away a spot for a tank or another damage carry rather then the utility she would bring being minor in a team.
Why take her top and risk going against 
who can screw u effortlessly ?
While it is a tempting idea to take her top and bully the shit out of those poor Tanks and Fighters who are ability based and/or immobile, others will also think just as dirty as u did and will pick one of those above.
Take her mid against Mages ( wish i knew why people keep picking them ... ) instead and, as long as u use E to block their key spells ( 
E for example ), u will never lose against them.
Things will get even better with the upcoming Nullifying Orb rune ( free 
shield that scales with ur tAD ).
SR ( ranked + normal ) is all about counterpicking ( either through kit design or champs with no weaknesses ) with minimal skill expression now.
