I made a Wiz->Cryo->Link->Ele (at ele 1 right now), and don’t really think it performs bad at all, at least in PvE (didn’t get to play PvP yet)
First off, Linker is pretty awesome. By itself its great when leveling, but in parties it shines. Theres a clear difference between not casting joint penalty and using whatever other dmg skill you have, or using joint penalty in terms of time to clear a mob. Its ridiculously faster to clear in a party when they are linked. So much so that when I go in dungeons I usually only cast joint penalty and then auto attack to save sp (and eventually cast ice pike/ice wall to save a bad pull), and you always see people asking for a Linker to join their party, everywhere. Linkers are the priests of the wizards
Secondly, linking adds lightning damage, as well as frozen enemies (with cryo attribute). So while you can cast hail to freeze and then eletrocute with bonus damage in any Ele 2 build, doing Hail -> Joint Penalty -> Eletrocute just melts enemies (in dungeons, because you actually won’t need this much increase in damage outside of them), you do basically do triple damage with eletrocute (+100% from Joint Penalty, since eletrocute is a single target skill with jumps, then +50% dmg from joint penalty lightning bonus, and +50% bonus from cryo on frozen). And all this while having a more “efficient” hail/eletrocute, since enemies are sharing damage, so if one of them gets hit all of them are damaged, so say goodbye to “killed 4 but 2 remained full half life after using hail/prominence” (im assuming a joint penalty gem to add 1 skill level)
Cryo also has lots of utilities. Ice Bolt is a low sp freezing machine, and freeze is one of the best CCs (increases damage received, can’t move or use skills). Ice Pike has good damage and is a insta-cast AoE freeze (which also benefits from +100% damage from Joint Penalty for some reason), and Ice Wall is just awesome… Hitting the wall does a ridiculous amount of damage against big targets (such as bosses), has good range, good angle and freezes the ■■■■ out of everything. It also scales directly with your Matk making it useful on all levels. Freezing by itself increases damage dealt by ~30% just so you know (you can test this auto attacking a frozen/non frozen enemy)
And finally, while quickcast is a cool skill to have, it doesn’t increases you damage, since the biggest concern are cooldown times, and not so much casting times (meteor for example has 90s cooldown, so it doesn’t really matters much if it is 5s or 10s cast). While linking enemies actually increases your party’s overall damage by a lot.
So the way i see it:
Cryo > Wiz 2 (by a longshot)
Linker =~ Wiz 3 (both are pretty good but depends on usage, Linker seems better for dungeons, while wiz 3 seems better for PvP)
Feel free to disagree with arguments!
My current build: http://www.tosbase.com/tools/skill-simulator/build/rzvh0up1is/ , going almost full int and a bit of con just to survive. I’ve no idea what to take in rank 7 and am open to suggestions.