Help me get a shaft

I've been playing a 76 gram UST Proforce V2 S flex with around 2.2 torque.  The last several rounds, on the front nine when I just kind of butter it, I get a nice maybe 5 yard draw.  When I try to get after it or when I'm amped a little especially on the back nine, I get this huge ballooning space-hook that ends up two fairways to the left.  I'm satisfied with my distance and am looking to eliminate that shot and hit more fairways.  Yesterday I hit the same shaft, but in X flex and 20 grams heavier with a torque of 1.6.  It felt like a freaking weighted training club, wasn't nearly as smooth and soft as mine, but all of the shots were less than 5 yards off line.  No matter how hard I swung, I couldn't really get it outside of that 5 yard width left or right.  The distance looked like my normal distance:  not nearly Bubba Watson, but decent.  I've always gone with the notion that you want as flexible a shaft as you can hit, and with a swing speed that tops out around 118 on the course, but is probably between 105 and 115 most swings, I figured S with the low-torque shaft would work pretty well.  Is the high ballooning hook indicative of a shaft that's too flexible?  I want the control so I don't mind giving up some distance.  You might say take a 3-wood, but I tried that (S flex, same shaft but fairway version) and still get the high ballooning space-hooks.  I'm also concerned about the weight.  They have an 86 gram version of the X in that shaft which feels like a much better weight for me.  96 is just a little too heavy.  Figuring that a heavier shaft will slow you down some, is there any other tangible benefit to heavier shafts for control?  Any thoughts would be appreciated...

No thanks to you guys I bit the bullet and bought this driver  .  It's the same one Stricker uses, but with a 10 gram heavier shaft.  It's so tight off the tee.  Distance was fine, ball speed low 160s.  Just so much tighter off the tee than any other shaft I tried (all S flex).  Even my bad swing only went 15 yards offline or so, about 20 yards shorter.  I blamed the golfer for that one.  Hoping to hit more than 60% of fairways this season...

I also solved the mystery of lower swing speed at Golfsmith:  wear spikes to keep from slipping on the mats.  I could actually bring my swing into the store.  It was nice.