FWIW, if you find a bourbon you like take the time to dig around on the Internet and find the mash bill.
Turns out ALL of the ones I've tried and liked -- Buffalo Trace, Elijah Craig, Evan Williams, Knob Creek and Wild Turkey 101 -- are low rye. And most of the other brands from the same distillery share similar mash profiles.
Knowing that I don't like wheats or ryes or Tennessee/charcoal filtration cuts this down to size quite a bit. So I've got a pretty long list of bourbons from 5 distilleries (Buffalo Trace, Heaven Hill, Jim Beam, Michtner's and Wild Turkey) that I'm a lot more comfortable dropping some coin to try.
My affinity for WT101 has prompted me to want to try the Rare Breed and the Longbranch, so I really get what you're saying, and you're right, it will make it easier to choose a direction, and I may have to go back and try Elijah Craig again, since Heaven Hill produces that and the Evan Williams line, which I liked more.
This is the website I linked earlier, and it goes along with what you're saying. The only Buffalo Trace product I've had so far is Benchmark 8, which wasn't bad, and I think I will go ahead and pull the trigger on the Ancient Age. The bad news is that the only size I can find around me is 1.75L, but the good news is that it will run me about $20. It should be fine enough for what I plan for it, and knowing it's from a distillery I've already tried, some of my anxiety about it has been alleviated.
After that, and restocking my WT101 soon, I'll probably roll the dice with the Old Grand-Dad Bottled in Bond, unless I find the 114 first.