What you should probably do is go to Keith Baker's blog and answer his Question Of The Week. But, since you're here, ponder this. Legendary film director Howard Hawks is supposed to have said that a good movie was one with "three good scenes and no bad ones." He directed the original Scarface, the excellent The Big Sleep, the classic Gentlemen Prefer Blondes, the genre-defining Rio Bravo... he knew what he was talking about.
That's a good rule for a game session. If you're spending a couple hours or more together, aim for three good scenes and no bad ones. We don't have to use "scene" in the pretentious artsy way -- any encounter, any combat, any problem-solving will do. If you have three exchanges that are fun for everyone, and none that are anti-fun, you're doing it right. Maybe not the way I'd do it, but you did it right.
This is kinda how I design adventures these days (and it's one of the reasons I'm a substandard module designer). Figure out where they probably start, figure out an interesting place that they could end, and then come up with around 3 fun-sounding encounters that the PCs could have along the way. Of course, they're not locked into anything other than maybe "here's where you start." If they don't follow the leads to my encounters, I have every confidence that they'll make their own fun.
But as a GM, I do think part of my job -- part of what I enjoy about running games -- is helping set up those 3 good scenes. And trying to thwart bad ones. The goal isn't for the characters to succeed at everything; the goal is for everyone in the game to think it was an awesome way to spend their time.
Another interesting Hawks quote to consider before you go answer the QOTW: "As long as you make good scenes you have a good picture -- it doesn't matter if it isn't much of a story." I don't agree, but that's for another day.