It's probably helpful that we got married in the off-season, since I hear there's quite the competition for prized summer dates. Everything was absolutely wonderful including the rangers who never signed up to be event coordinators, but still manage to make sure everything is perfect.
We were warned that the roof leaks when it rains, so I was a little worried when it rained the night before after we'd set everything up. When I went in to the hall in the morning, though, nothing was wet, so it's obviously not too bad. The patio heaters were in need of servicing and didn't do a great job at projecting heat into the pavilion, but everything else was functional.
We ended up with around 130 people in attendance and it was rather cozy. We served our food buffet-style on the picnic tables in the "catering kitchen" and had tables/chairs set up in the pavilion for outdoor lounging, but everyone fit comfortably at long tables, even with a band, DJ, card/gift table, and trail mix bar set up in the hall.
The rangers can come off as a bit gruff, but they're big softies at heart, especially if you're not overly demanding of them. It's important to remember that these are park rangers, not event coordinators! They made sure we had what we needed, they whisked away the unused tables/chairs before our guests arrived, they quietly handled parking issues without me hearing about it (except when a tree damaged in the previous night's storm was leaning precariously over a guest's car, where they had us interrupt the DJ to make a timely announcement!) and let us have our fun without interference. One ranger was worried our band might draw noise complaints, but the low off-season camping attendance and the fact that I'd reserved all the cabins which face the hall probably helped in avoiding that issue, since there were no requests to lower the volume of music.