Ahh excellent thinking, however spell flux has a flat cooldown of 14 seconds, overload will ad more CDR, which you need, and the rune prison will keep your enemies snared for a longer duration i.e. out of position. While leveling e might seem prevalent due to the increase damage I believe you can achieve better results with a q max to start at least. AS you stated you are relying on the sheen's passive, which does physical damage, so reducing enemy magic resist seems like something to consider late game when you have more mana and are dealing magic and physical damage.

Excellent point Grandmaster Freak, however, being ADC Ryze, your damage outpoint relies off of exploiting the passive from Sheen. So it is ideal to have short cooldowns, and how Ryze's passive works, it is important to level up the skills at basically the same pace for AD Ryze because you don't get much spell benefit but basically are just using them to get your Sheen to proc and therefore the even build approach is most efficient!

Why don't you max w and q with a point in e early?