Got 2 Reflecting Mists and 1 Hinekora's Lock in SSF. What's the best FRoSS ring I can make?

Playing self-cast FRoSS for what it's worth. POB for what it's worth: https://pobb.in/mo-nW0sgB_Xu

I haven't used a Reflecting Mist before so I'd love some guidance.

I'm guessing my best option is a Cogwork/Helical ring with something like Flat ES, Crusader %ES, Crit Multi, and an attribute?

If I can't get a Heist base, a Crusader Moonstone ring? What's the best way to set it up for the Reflecting Mist? I've seen people benchcraft things like Endurance Charges to minimise the risk of very negative mods, but haven't fully gotten my head around all the crafting principles.

I'm currently using this Iolite Ring for stats: https://imgur.com/U1HrNJp