For what it's worth, I'd go with the standard drivetrain (option #1). That gives you a GI range of 17" - 96", which is pretty good. You could go a little lower if you plan to use it offroad or like to ride up hills at walking speeds.

The jump between the 50 and 34 is going to be huge. If you don't need super-low gearing and don't mind a big jump on the front, though, it could work.

I happen to currently like barcons for triples. They're a little less expensive and more robust, but I wouldn't worry about it unless you plan to go offroad a lot.