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

95+dB is really the place to be. But I get flack for even saying 92. That to me is rock bottom. As I suspect you are now really beginning to understand why. Your Raven is an absolutely fantastic amp, but one rendered out of bounds and unsuitable simply by the shortsighted decision to buy inefficient speakers.

That one move dooms and limits you forevermore to a hundred watts, minimum. Even then it is almost impossible to get the kind of effortless speed and dynamics you are going to be hearing, in spades, with Double Impacts.

But think of it, that Raven/Tekton combination is only about $6k! Which if instead your speakers were a typical 89dB could easily be 3X the money and still not get there! Not in SPL, not in quality. The typical 89dB speaker requires nearly ten times the power to do what your 98dB DI will do. People really should do the math. 20 watts and 98dB speakers, or 200 watts and 88dB. Which do you suppose you can buy higher quality with $3k? 200 watts? Or 20?

Then with the money you save not having to buy hundreds of watts you buy Pods, Podiums, turntable- now you are in heaven!

Methinks something is wrong with your subwoofer. It works flawlessly in this review...
https://hometheaterhifi.com/volume_4_4/velodynehgs10.html

Unless I am misunderstanding, the sub out on the amp is a high pass xover just to remove the low frequencies from the main speaker. You would still control the volume of the sub with the control on the sub. You actually wouldn’t want that output to be variable.

Ok, understood.
Why not use the sub in a traditional hookup with the low-pass crossover? The mid bass driver on the mains is going to present better SQ than a subwoofer driver. Set the crossover on the sub and use it for the lowest octaves.

{On the back are an ungrounded AC socket, RCA line-level inputs and high-pass (80 Hz, 6 dB/octave) outputs, Volume control, Low-Pass crossover control (40 Hz - 120 Hz, 12 dB/octave initially, 48 dB/octave ultimately), Crossover in/out switch, Phase toggle (00 or 1800), Subsonic selection (20 Hz or 35 Hz), and a remote sensor switch.}

"I was really curious what 95+db speakers were like so I borrowed a pair of whatever klipsch’s... RF3’s? He picked them up for $200... they mopped the floor with the salks and they are not even close to the same level as the Salks, so it was the sensitivity / synergy that was doing it for me."
Did you try using the Belles Aria with those speakers?