Cottage wedding

FH has a family property, and we are considering it as a venue. It's co-owned by his aunts and uncles, and absolutely beautiful. We love it there and spend most of our summer weekends up there. It's been a meaningful place in our relationship. It's about an hour and a half from where we live. Those are the pros.

Here are the cons.

1. Our absolutely minimum salt-the-earth everyone's-parents-are-pissed guestlist is about 90, and there are no big flat spaces to put up a tent. On a rainy day we'd be putting 90 people either in a small boathouse or spread out over five cottages?
2. It's an hour and a half away from home - we'd probably have to take the week off work to make sure everything was set up the way we wanted, and I'm a teacher so that means a summer wedding rather than fall, which was what we'd been talking about.

What would you do?