Remember a few things.
AF assist beams have a working range, typically only useful at closer distances.
AF works hard only when your pointing at something in low light. You may shoot from the back pews of a church in a dark and moody area, but the couple is upmfront in good light. That good light will help you focus.
I think this will be a learning experience, Vinz. I do not profess to be a pro, I only have about 10 weddings under my belt and all as 2nd/3rd shooter and I do grip work for a major studio in town here, however nothing beats in hand experience.
IMO, keep the macro for outdoor good light, work the 1.8 85 for what it's good for, moderate low light AF tracking.
Just my .02