I'm gonna go ahead and toss in my 2 cents as well... if you want all-around versatility, choosing the shorter rod is going to limit your capabilities. I'd go with the longest rod I could get my hands on. I'm fishing an 8'4" TLS Power Matrix 3 wt these days more than my TFO 8'6" 4 wt, and I can tell you that I wish my TLS was longer!
BTW, if you ask Jim Casada what he'd pick, he'd lean towards the longer rod, and you won't find many folks alive that have fished more in the Park.
One last note... go with your instincts. If you know what you're doing, you can catch trout all day in the Park on a 6' cane pole. Get the rod you'll be most satisfied with.