Hard to say without more qualification than "36" 140 watt speakers". Typically, however, the speakers which came with "rack" systems like this were never "surprisingly" good and, given that Kenwood built their reputation on components other than speakers, it's likely they look more impressive than they sound.

So with that as a starting point, I would venture that 15 years of improving speaker technology would give you a number of choices in smaller speakers that sound more accurate. One thing to consider is that most smaller speakers (but not all) have a hard time pushing out "I can feel it in my seat" bass. On the other hand, it's quite likely that shortcuts taken in designing your existing amplifier or speakers limit their ability to play that low, anyway. Unless you're a fan of pipe-organ concerts, disco, or trance music, you probably won't notice what you're missing if you replace bigger speakers with smaller ones.

As for adding speakers, most of that depends on your amplifier -- whether it will accept additional speaker connections (likely) and whether it has enough power to drive the speakers you select (also likely, unless you buy some very low-impedance speakers which may cause problems with the amplifier).

Your best bet is to gather a couple of albums that you really like and know well, and go to the stereo store. I hesitate to recommend big-box electronics stores for this because their setups generally are nothing like what you have at home and because, frankly, the best-sounding inexpensive speakers rarely will be found at such stores. Tell the salesperson what model amplifier you have and how big your room is and go from there. Have fun!

Wow. Thanks for the great advice! Will do as you say! Moo.