Thing is though, many things have been changed this patch. There are no more auto-suns and clone doesn't hit like a truck anymore. This would already turn the tide of a lot of battles, I would have thought. I agree that there are many variables in any fight and I'm not disputing that up until now Wizards had too much of an advantage in PvP, but I think too much was changed and has tipped the scales the other way, rather than meeting in the middle.
I'm not sure what you have in mind when it comes to a "middle ground" for casting speeds as timing is a rather precise thing here anyway, but I do think that spells should be looked at on their individual merits, and it's my view that most of them were just fine. FF needed slowing down. It might be an idea to do the same to Vamp. I don't like the idea of FD being slowed down because it's a main mob nuke spell (FD for living, Tbolt for undead). Again though, I don't think being able to cast faster unbalances PVP or makes it impossible for Warriors to win. The auto-suns and clone damage (both removed/reduced) were a far greater factor there. Remember, it doesn't matter how fast you cast if a warrior is out-maneuvering and evading you.