More power to you. The improv element allows everyone to buy in. I like the way you said it: [Savage Worlds] giving them the sense that they have agency in the universe.

There's probably a happy middle-ground between planning and improv, but the longer you play tabletop games the less planning you probably do. In improv no one walks on stage with zero prep, years of experience has gone into tricks and methods for heightening scenes. I'm sure the same applies for for tabletop role-playing games.

I checked out "Savage Worlds" from Pinnacle Entertainment and downloaded their 'Test Drive' rules. I'll play it with a few friends; if the first time is a wash, I'll use a 'Bennie' and try again!