Finally found a space for the speakers I’ve been storing... and I don’t love them any more

I had a pair of Paradigm Titan Monitor v.6 (the last of the line, built in Canada). I had them paired with 1990's Rotel separates and they were a bit too intense. When I upgraded to an Arcam integrated they smoothed out and sounded like different speakers. I upgraded to a pair of Revel Concerta2 m-16's and the Arcam was no lonegr cutting it. Too low-keyed and a bit under powered. I switched to a Cambridge Audio integrated and the Revels opened up and sounded more spacious. I am convinced that there has to synergy between speakers and the electronics driving them.

spenav, No I have not heard the Persona line myself.  My friend was suckered by their dynamics and bought a pair and hated them when he got them home.  As others have said, too intense.  He turned them back in for a pair of Wharfedale Elysians.  I have heard some of the other Paradigms and was less than impressed.

Don’t overlook the Revel Performance 3 226Be.  Even more of that transparency and less bass bloom than the bigger 228Be. I presume you have subs to over the bottom octaves. 

mhsu, it is just as likely that it is the room you do not like and not the speakers. Move them temporarily to another room to listen before you ditch them. If they sound fine in another room you have a lot of work to do.

Thanks for all of the terrific feedback. Taking @douglas_schroeder @roxy54 and others' advice I did try swapping out components to see if it was an amplification preference.

I have done this exercise before, but it has been a while, so I brought the Revel bookshelf speakers into the other listening room to do some testing. (The Paradigms are too big for me to move by myself, so I haven't had a chance to do the converse yet.) The results somewhat surprised me.
It turns out Douglas et al were right on a number of counts:

First of all, though I did still prefer the character of the Revels, the differences were not as extreme and pronounced as I had recalled when matched up side-by-side with the same electronics.
Second, I also found that the Paradigms did sound much closer to what I wanted when paired with a different amplifier. I tried powering them with a Peachtree Audio Decco 65 and they presented a much more transparent sound with greater separation of instruments and more deliberate positioning in the soundstage. I had not tried this in the past since my receiver (an NAD T758) and the Peachtree integrated amp only deliver 60-65 wpc, whereas the Adcom supplies a hefty 300 wpc. Indeed, I would still want more power than the Peachtree can deliver, but the difference in the character of the sound was unmistakable. [I will also follow up with the Anthem receiver which is normally paired with the Revels, but there is a lot of plugging & unplugging that has to be done for that to happen!]

I think the other differences I heard between the Paradigms and Revels can be chalked up to what everyone else has mentioned -- much newer, well-designed speakers and room treatment.
I have already learned a lot and there are many opportunities to tinker and upgrade (and spend money). I think my next step will be to audition a few amplifiers before making a move. In a totally emotional and irrational way, I'd love to make the Paradigms work (and it feels like I can), just because I've wanted them to for so long, but there is clearly a world of options out there.