Man i feel your pain with that adapter setup. Its honestly a nightmare when you spend that much on a body like the R5 II just to have the lens wiggle or hunt for focus right when you need it. I had the same disappointment trying to adapt my older L glass since the connection felt so flimsy during vertical shots. The EF motors just arent snappy enough for the new dual pixel AF and unfortunately that clunky feeling with the adapter is pretty common once the mounts get a little wear on them. If you keep using that setup for a Seattle wedding, you are gonna be fighting the gear instead of capturing the moment. If you want one lens that stays on your camera for basically the whole day and wont let you down, you gotta grab the Canon RF 24-70mm f/2.8 L IS USM. Its usually around 2399 so its right in your budget. The autofocus is near-instant compared to the EF version and the internal communication is way faster. I tried to make the Canon RF 24-105mm f/4 L IS USM work to save some cash, but the f/4 aperture was really disappointing in low light reception venues. It just didnt deliver the bokeh I needed for those high-end portraits either. Methodically speaking, the 24-70 is the only logical choice here because it handles your wide group shots and then 70mm is plenty for those mid-range candids. You wont have to deal with the focus hunting anymore because the Nano USM motors are designed specifically for the R5 series tracking. Just get the native glass before that Seattle gig or youre gonna be stressing the whole time... its not worth the risk on a big job.