This is why I treat the rules more as a series of suggestions. I'm not letting the rules lock me into something I think is stupid. That's probably the main benefit of forums like this one, to see how other GMs manage their big book of homebrew.
That said, I also tend to run campaigns that are either stealth intensive or not and characters are generate to match. In the former case I handle things a little differently. For a non-stealth heavy game the party roll is my fall back mechanic.
I do not use party rolls for surprise though. If you made a character designed to most often go first and generally not be surprised I'm not to wreck that by rolling a party roll, and I don't tend to differentiate there based on campaign feels. That's the same reason I don't use group stealth checks in a stealth heavy campaign but I do in other campaigns. When everyone has rolled up a ninja they can be that, but in a more normal party I'd rather roll group checks and allow the one or two stealth capable characters to help the party succeed (or they run out ahead all stealthy-like, whichever).