Please evaluate my system...

@tim_field, Regardless of any type of power conditioner used dedicated 20 amp circuits runs with 12 or 10 gauge wire depending upon the distance and ones personal preferences is a must in my mind if its a possibility within your home. That one change will improve the sound of your music. Good AC quality outlets are also important.
I totally understand that the origional question you asked was centered upon compoient upgrades however the foundation of any construction site is extreamly important.

If it's bigger sound stage you're after, have you tried speaker placement?

I have stock DL103R cart in my system. My soundstage is wall to wall with excellent imaging and detail.

Just for comparison, my system is DL103R on Linn Axis table with Linn Basik tonearm, to Electrcompaniet step up transformer to Audio Research sp16 pre-amp (tube) to BEl Canto Ref1000m amps to OHM Walsh 5 series 3 speakers which has similar lowest impedance specs.

Take a look at the ref1000m amp specs online. You will see where this mates well to the ARC tube pre-amp (100kohm input impedance) and is also well suited to control and  drive the speakers well in that the damping factor is fairly high, which is a big + for the OHMs in particular.  

It’s impossible to know exactly what something will sound like without actually hearing it, but from what you indicate, were it I,  I would very much want to hear what a different amp perhaps better mated to pre-amp and speakers might sound like in your setup. I would expect better detail, more balanced tonality, lower distortion and larger soundstage going in.

Another cartridge, not that the one you are using is bad but a different prospective is always entertaining.

If I was to improve that setup, it would definitely be the front end. 

Michell Gyro SE
Lyra Delos
Parasound JC3+

Denon cartridge and Linn Linto are the weak links by far.