Found a Heaven’s Light - What to socket it with?

It’s got two open sockets. I’m offline SSF Holy Freeze Zealot.

With it equipped I’ve got 40% increased attack speed. Judging by the IAS calculator the next breakpoint seems to be 46% IAS, and with two Shaels I would go to 80% IAS, meaning from 2.11 attacks per second to 2.65 attacks per second.

Is that worth it, or should I socket something else?