What are your thoughts on optional content in a published adventure?

I'll be publishing a short adventure in the near future (just waiting on some paperwork at the various marketplaces), and am planning for the next larger project. A number of the possible projects all seem to have a bit of an exploration or sandbox theme and end up feeling a bit like "choose N of M" side quests, during a middle portion. I.e. the adventure would contain more content than I would expect any single gaming group to encounter on a play-through. The GM side of me like the idea as there's usually something that I can tell wouldn't quite work for my group, so having pre-prepared options could be nice.

However there's also the aspect of "Why am I paying extra for content I won't use". If there's a large amount of optional content, I can easily see having an assumed set of choices in the adventure and an optional extra sourcebook of side quests. For instance a chose 2 of 6, having the assumed 2 in the main book and then 4 extra in a side supplement would make sense to me, but a choose 3 of 4 would have all four in the main product.

What are your thoughts on adventure/product structure for longer adventures/mini-campaigns that aim to allow more player choice in how they navigate the adventure?