I can share my recent experience that may help you think this through. I had one removed from my right parietal lobe around this time last year (attached MRI image). It was also fairly large, but the concern was more about the location than size. In my case, it was positioned directly over my sensory strip (adjacent to the motor strip).
I went through about 4 different opinions from well-respected neurosurgeons. Half of them did not recommend surgery, due to the area it was located. Hence, these folks recommended gamma-knife (or cyber-knife) since it was mostly symmetrical and easy to target with radiation. The ones that recommended surgery, felt gamma-knife actually makes it more difficult to recover from a surgery if the gamma-knife had failed to eliminate it. According to them, the radiation kind of "ages the brain tissue" and makes it harder to recover from deficits that could result from a surgery.
Embolization was never advised to be used alone in my case due its size. The approach to embolization differed depending whether gamma-knife or surgery was the elected approach.
I ended up choosing surgery, mainly because I wanted to get it over with. They did embolization 1 week prior the surgery, and then an additional embolization the day prior to the surgery to finish turning it into a "rubber ball." The 2nd embolization did cause sensory deficits in my left side, but these were risks that I understood going into the process. The surgery that followed was supposed to take 6 hours, but ended up taking ~12 hours (they went back in after discovering a smaller 2nd AVM beneath the larger one). It took about 2 weeks of intensive rehab and 6 months to feel completely normal again (minus mild sensory deficits on the left side). Overall, I do not have a single regret.
My advice for you is to get several more opinions if you haven't already done so. In my experience, the first two surgeons I met had completely divergent opinions. Time is on your side. In other good news, I was often reassured that larger AVMs are less likely to bleed. I am confident you'll find great care and make it through this!