An honest opinion about upgrading?

IF the volume levels which you are obtaining are satifying to you; much of the improvement you desire can be had via NOS driver/phase splitter tubes in your power amp. For definition and clarity, I'd personally recommend a pair of Siemens ECC83's, and bottom gettered Sylvania 6SN7GT's, from the 40/50's. The same 6SN7s can be used in the pre, but they have to be graded, "low noise". Some examples of what to look for, that won't break the bank: (https://www.tubeworld.com/12ax7.htm) (http://cgi.ebay.com/Radio-Tubes-1-Sylvania-6SN7GT-6SN7-Tube_W0QQitemZ350241000213QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item518bfd8b15&_trksid=p3286.m20.l1116) Installing dedicated power lines from your mains(I used two parallel runs, twisted, of 10AWG) will improve your system's dynamics. A pair of Synergistic Research AC Powermasters on the pre and main amps will offer greater definition and imaging improvements(If the speaker/room interface is up to it). Kimber Heroes, Silver Streaks or KCAGs will also help you achieve your goals, as they are more transparent than many other cables in the price range you mentioned. Where were the output tubes manufactured? If Chinese; you may consider a set of Winged 'C'(St petersburg plant) KT88s, ie (http://www.upscaleaudio.com/SED-quotWinged-Cquot-KT88_p_4.html).

ICs, then amp (s). room treatments too need be investigated.

Better ICs will aid clarity though only to the degree your gear possesses. take care not to attain ICs which pronounce or acentuate the top and bottom end only as a false impression of gain is sure to follow.

Amps, or better yet, power, means control. Having great control of the speakers will sure enlist more clarity, less sibalence, tighter bass, better imaging and sound stage recreation. Mono blocks are usually a plus over stereo amps if no power diffs are had due to having dedicated power supplies per ch. Normally it is a decided improvemnet and very noticeable.

I heard the Paradigm on some hefty Mac gear and the more power applied to it from the MC252 to the MC 602, each gain upwards in amp alone made the sound better overall. I feel the Paradigms like power... or acted like they did.

Tubes, cables, and treatments will all help you regardless and thus a worthwhile bit of time well wasted. but I suspect at 90 - 150wpc, a sure gain towards your aim is to add some greater power and SS is likely going to come cheaper per watt than will likewise tube gear.... and again, I suspect the Studios will enjoy it.

Normally, I would suggest you optimize what you have and treat your room to get the most of your soncis, but in your case, I completely agree with Shadorne..you need substantially more power for the Paradigms to sing.

Not familiar with those speaks and amp, but if those speaks are a difficult load as indicated and the amp isn't up to it, that is the place to focus. Look for a high current amp that mostly doubles output into 4 and 2 ohms. Class Ds are a possibility. The better Musical Fidelity amps second hand are a very good value that might fit the bill also.

In the same vein as Shadorne and Mapman my recommendation would be high current electronics.