Well if things remain the way they are in Shiradi, there is nothing stopping a little cross class splashing to get MM SLA on a lot of different builds. Its cheap and first tier. There are numerous easy ways to get spell power.
Taking MM for crazy dots or CC (you would have to be in Shiradi for nerve and twist in double rainbow and prism for dots).
There is going to be a significant upgrade to dps for certain builds (including some builds getting no mercy which may stack with sense weakness). You could run in Shiradi and spam magic missle then take advantage of the CC to due tons of damage with twist sense weakness.
I was already thinking about doing a 6/6/8 Monk/Wizard/Fighter Elf. You could get haste, Displacement, MM CC etc. Be nice that you can splash the CC uberness and dots on melee. Truth be told there is no reason you could not put enough points into a tree to get good spell power and still get the top of another tree, especially if you do not Dumpstat int.