Think I agree with Taz on this one about swing weight.
I attack my clubs semi regularly (particularly the driver). Shorten, lengthen, thin grip, super thick grip, change shaft - flex & weight. Never once have I measured and have only briefly considered swing weight. As long as it 'feels' OK then it's fine. There is no need to worry about getting it back to 'original'
OP about stiffening up - 1" of the top won't make a massive difference to the stiffness IMO & experience. It will do something technically measureable but doubt you would feel it.
Opinion on shortening - no brainer, should do it.
I currently play 44 1/4" but have experimented all the way up to 46" (or 48" can't remember of the top of my head what is the legal maximum in the Rules of golf) in increments.
I gained no noticable distance on the longer clubs, felt awkward(ish) and sprayed more. Shaft length has been increased so a robot can hit it further and aid claims of 'EXTRA LENGTH (shaft or hit??) & FASTER CLUB HEAD SPEED'.
Around 44" is long enough to whack it out there nice and straight and in play (a must at my course). It also makes it easier to fit in the boot . Get your saw out, chop it, re-grip and give it a go. If all else fails you can extend it back out a bit.