The part about who you're riding with is huge. I would say it's the first thing I think of before conjuring up anything. That helps to set up the distance, terrain, pace, etc. 80% of my rides have been with a partner or group, and all of those were 1 or 2 night trips.
That's a really good point!
I still like designing a trip and then asking - or SteveDoom calls it "pushing" - the appropriate folks to go on it. And, sometimes they have great things to add.
I'm lucky in the sense that all of my trip partners are always in better physical shape then I am. So, by default I don't have to worry about that stuff. Where I do have to worry is in regards to partners mental and emotional "shape" - mostly in regards to lack of experience. I've always found that to be more problematic.
NWhen someone asks you what to wear/do when going out for the day, you can't really give an answer other than "it will be 37 degrees and a little bit windy" or "it's 50 miles with 4,000 feet of climbing."
lol. True that!