Cutting an inch off the butt end of your driver shaft will not stiffen it enough for you to tell. If you were putting that brand of shaft in your 3 wood, you would make the final cut on the butt end. A 3 wood is a bit stiffer then a driver with the same shaft, but you would need a frequency tester to see exactly how much. As for your other questions, you are at the point where taking up clubmaking/repair as a hobby is now something to consider. Especially if money is a concern. The big problem with shaft selection, and what is right for you or anybody else, is the industry has no standard. One company's stiff is another companies regular. Now throw in the bore through hosel to the equation and you will begin to see my drift. The best thing I can recommend is to try and find some clubs that have the shafts you are interested in and test them on the range. Even if you have been fitted, testing on the range is still the best way to make a decision. Welcome to club customization.
Having said all this, I like the Innovative Sports Technologies Graphite shafts. Around $60.00 per shaft, and with your swing speed I would look at X-Stiff, that is what I use.
Hope this helps.
http://www.clubmaker-online.com/innovative.home.html