My thoughts...
The Westy is a hefty chunk of guitar. Substantial is a word that comes to mind when compared to the DC22. The neck is obviously a little longer (24 frets) and the neck angle is a hair less than the DC22 - which is probably a function of the trem vs stoptail bridge. The Westy neck carve is slightly deeper but it's hard to tell the difference and I am notably sensitive to neck carves - preferring them as wide/fat as possible.
The DC22 has a shorter neck (22 fret) but there is no real difference in balance between the two guitars - which surprised me - but it makes sense now that I think it through. To be clear, the headstock of the DC22 is literally closer to the body by about 3/4 inch. Since the Westy has a big hunk of brass in the body (the tremolo) to counter the longer neck versus the DC22's stoptail and shorter neck, they feel about the same hanging around my neck (balance). From a fretting perspective, I can't feel a whole lot of difference between the 22 and 24 frets on the 24.5" scale.
Tonally speaking, these two guitars are too different to give you an apples to apples comparison. My Westy has been heavily modified and the uncovered 59/09's are the 4-lead variety (for 5-way rotary switches) which sound a little different to me in split mode than the same pickup with a single coil-tap lead (for McCarty switching). My Westy also has the artist tweaks and the new-style nut (made from different material).
My Westy (and, perhaps, stock models) is very well suited to rock/metal with full and open tone and it is super resonant when played acoustically. And it kills the texas blues tones when I use the neck pup in single-coil mode.
The DC22, by physical comparison only, is a delicate flower. It is notably lighter. By tonal comparison it is just as punchy but the covered 59/09's are more complex. If the Westy is ideal for the raw power of the HX side on an HX/DA amp, the DC22 is ideal for the DA side. The Westy makes me want to dime the amp and lean way back - arena rock style. The DC22 makes me want to find that sweet spot on the amp that gets me the most expressive range and get emotional.
The West Street Limited is, in my opinion, still one the greatest PRS guitars to leave the factory. They are selling for around $3500 used which I think is a steal. They have dark Brazilian Rosewood fretboards, hidden fret tangs, super colorful birds (paua or abalone?), small eagle inlaid on the headstock, Om truss rod cover, and that classic little Dragon inlaid on the Sapele (unique to this model) top. My only worry is that they'll really catch on before I have a change to rat-hole another one.
Although the DC22 has less bling (by design), it is more exclusive. Only 105 currently exist (I believe) compared to the 300 West Street Limited guitars PLUS the regular West Street guitars without the dragon or Brazilian. No idea how many of those are out there. Of course, Musician's friend may-well make more DC22's but they haven't sold very well (surprisingly) so who knows. The DC22's maple top will yield a brighter (generally speaking) tone over the Westy's Sapele top. The DC22's dark East Indian Rosewood fretboard is really nice but it isn't quite as smooth (due to the increased pores) as the Westy's BRW fretboard.
If I were going to spec-out the perfect Westy, I would change the metal tuning knobs to ebony to help keep it physically balanced. and make sure the body blank was heavy and the neck blank is light. I'd use ebony tuning knobs and use the 4-conductor/uncovered 59/09's.
The DC22 seems perfect as a stoptail with covered 59/09's so I'd REALLY focus on making them with the heaviest body possible and the lightest neck - while maintaining the Santana carve. Ebony tuner buttons are a requirement too - to help keep it physically balanced. I've said before... the DC22 would be insane in gold top (and dark back) with P90's (or 408 bass pups), the PRS 2-piece bridge, and super thin nitro finish.