All this riven buff ranting and I'm here like....
JAYCE WILL BE TOO STRONGGGGGGGGGGG 
JAYCE WILL BE TOO STRONGGGGGGGGGGG 
:D
He's still gonna have to get close to do his damage which will just = dogpile on Jayce.
Talking about his crazy lane damage. His q does shittons from reaaaaaaallly far range for poke anyways.
His Q poke isn't being buffed at all from what I saw. It was the AA buff in range and mana costs in hammer unless I missed something. And both of those are fairly short range.
You're talking about him having to go in melee range which is not true. He won't get dogpiled on if he stays from range and still uses his massively strong q
They didn't change anything about his Q gate shots in the notes I saw. They only did changes to skills that will put him closer to enemies when used. They are trying to get Jayce to be more of an all around distance fighter instead of just a poke machine.
Honestly i dont see the buff. Before patch i was dealing 300 magic damage on a creep with his R. After patch im still dealing 300 magic damage on creeps with R lol. Full AD build with 505 attack damage on each game.
That's because the change is supposed to be a buff to his mid-late game. The problem is that late game, you rarely ever want to be in melee form for any reason apart from finishing someone off or peeling an assassin off of you (in which case you're probably gonna die anyway if no one's around to help you).
It's an "okay" buff, but definitely not one that's going to push him over the edge, not in the least. As long as he remains weak against assassins, I don't think he'll ever get out of hand unless they buff his Q or W.