Yeah, Harlequin is def. the way to go when your pets damage doesn't matter and magic damage is the issue. He protects and shells himself, so Crashing Thunder was doing 40~ damage. Attachments were:
Strobe 1/2
ARK 2/3
Magic Jammer 2/3
Reactive Shield
Mana Tank 3
Armor plate 2/3
Optic Fiber
Heat Sink
I was only doing Hurkan and not Cailihm, so results aren't perfect. But basically, Fire/water/light and I never had to use repair. Also he was doing a pretty decent job of keeping hate off of a rdm and mnk that showed up. Pretty please with him, overall. Also, he cures himself at lower hp. Because of this, I feel it might be worthwhile to actually use some of that automaton cure potency gear we have been getting. Dunno though.
While VE can tank magic fights just fine, I quite enjoyed Harlequin's performance and also the fact that he was still enfeebling, curing me and hasting me.