Raven Blackhawk LE... am I going to be disappointed?

Yes it’s easier with high efficiency speakers because your choices will be limited.   Not necessarily better but a different way to roll. 
The facts speak for themselves.  High efficiency speakers are a niche for a reason. That is because to be efficient and full range they have to be large and often expensive,  things most do not want these days.  Also Tekton is not really high efficiency though more efficient than many. Klipsch heritage line designed a long time ago when only tube amps were available are.   There are others but again very large and very expensive.  
So really the “high efficiency” solution being pitched is not even high efficiency compared to others that are like the Avantgardes of the world. More like somewhat higher efficiency.  Which is fine if that fits the bill.  Add a sub and crossover like with many  and no problem. 

Never said you or anyone cannot build a beautiful satisfying and excellent sounding system with 87dB or whatever speakers. Simply said you are making it unnecessarily hard on yourself to take that approach.

It's only "unnecessarily hard" if there's no real benefit to doing it another way. Got it.

I power washed my deck, waited a few days for it to dry sufficiently, and today I applied a coat of beautiful semi-transparent, natural cedar, oil-based stain. Approximately 36 hours from now I’m going to do some serious victory laps of my own. Meanwhile, my 86db Sonus Faber stand mounts are sounding wonderful powered by a surprisingly robust Chinese SET integrated. I had the windows open and was rocking an average of 88db’s according to my Radio Shack meter. Sure helped make the deck work a lot more pleasant.

YMMV

I always thought efficiency and sensitivity were different.  And they are!
http://www.sengpielaudio.com/calculator-efficiency.htm

That's the technical explanation for why Krissy magic works especially well inside speakers. So much energy is wasted that if you improve electrical efficiency even a tiny little bit it results in big gains releasing tremendous dynamics and incredible inner detail.