Thanks much everyone for your input.
I found the issue of why the SS8 was not as involved, detailed, or textured as I would have expected it - this took place from the midbass-midrange area and the midrange-treble area. Despite this, I could sense that these speakers can reach an upper treble area this is not possible on my current set of speakers. All of this was noticed when watching a baseball game (as the first sounds to be injected into the speakers) after hooking them up. But those sounds were far-and-few in between. The speakers were placed head-on with no toe-in. Bass was not a concern with the issues I was facing with these speakers.
I knew immediately that there was an issue with the speakers, not the gear itself, since it does put out lots of detail.
First - to answer a few questions -
I think you might be barking up the wrong tree automatically jumping to crossover changes from jump street.
You may be surprised. I had purchased a set of used speakers that sounded good, but something was not quite right about the sound. A recap of the crossover snapped those speakers into place and were humming. (I understand that a cap rebuild cannot overcome a bad engineering or parts design in a product, but this was not the case.)
As a quick aside, have you recapped your Onkyo gear? That stuff is from the 80's correct? Might be well overdue for a recap if you haven't ever done that as of yet.
Yup. Due to age of the amp, I did that years ago with the electrolytics, and replaced some polystyrene with film caps. The only thing I did not recap was the filters since those look to be in good shape and would have been a hassle to replace. After the recap, the amp sounded smoother (electrolytics) and the soundstage became more wide (film caps) - the wideness is apparent when watching films.
I also played with toe-in on the SS8 the following day. The detailed upper-treble was a bit more apparent (not by much), but the mid-areas of the sound and texture were still lacking.
Thanks for your input Kingdeezie.
Those 8's deserve much better electronics in front of them.
Totally agree. There is no 1980's gear in existence that would be expected to deliver the quality signal the SS8's can handle. Time to spend some more money on electronics. 
Ah my friend... you may want to think again. There is a reason why vintage gear is loved. I have an Anthem Statement Preamp Processor - one of the best Northern American Made Preamps out there. Comparing both Preamps in stereo mode, the Onkyo Preamp edges out the Anthem for being a bit more airy and delivering a bit more bass. Anthem Statement is a heavy hitter at sound, and it is great at surround sound, but for stereo, I prefer my Onkyo preamp (which is 2 channel - it does not handle surround sound). If the Onkyo M-508 were produced today, it would cost as much as an Anthem Statement P-2 (perhaps even the P-5) and even some of the Emotiva Amps that are currently out there.
Great 80s gear brings to the table a level of detail that is comparable even with todays gear - amplifier and stereo preamplifier technology has not really changed all that much in the past 30 years. So I would put it up with the McIntoshes, Krell, Anthem Statement, and Emotivas to see how each would compare. It would be fun to compare them together!!!!
My power amp is 55 lbs, so it is no slouch. But it can be regarded as a paper clip compared to some other amps which are much more heavier (McIntosh, Emotiva, Krell, Onkyo Grand Integra M510)
