Area '58s and the True Velvets each have their own slight nuances in tonal variations, some like one kind and others like another. The major difference between the two is that the Area '58 has noise cancelling technology, while the True Velvet is a true single coil (which includes 60-cycle hum). It's all up to you, but if you go with the Area '58s (or any noise cancelling pickup for that matter), make sure you check DiMarzio's site/customer support for proper wiring diagrams, I think the noise cancelling pickups need a different wiring because of the noise cancelling technology involved.
I also forgot to mention, you might want to look into the YJMs- they retain a very single coil-ish tone, and you can still slop on loads of distortion. For sound clips, listen to pretty much any yngwie malmsteen recording.
Also a cool single coil you might find interesting, and which I think would be best suited for you, is the chopper for neck and middle, or pro track neck (if you want more humbucker-ish tone) with another single coil of your choice (Chopper works great here) in the middle.
ALL single coils work well for rhythm work. DiMarzio shows solo work on individual pickups because it shows the pickup's characteristic a little better on single notes, I guess they think more so than chord work (although I feel chord definition is essential to a pickup).
Now, the Evolution will still work in mahogany- take a look at Vai's "Red Lace", it's just that many don't feel the tone is that great. Although, I don't see how the Evo2 won't work in mahogany tonally (all though I've never tried or heard it, it might sound like poop).
If you want more bridge pickup options, I'm a fan of the Norton. Or, if you'd like to try it, the PAF Pro is a great all-around pickup. Go to DiMarzio's site, and all high-output pickups (save for the Evolution and Evo2) should work in mahogany tonally. Some pickups also worth looking in to: Super 3, D-Sonic,
Tone Zone, Steve's Special (if you want that voicing)
The Tone Zone is a cool pickup. A lot of people love that pickup. It does sound cool, and if you do go with it, remember this: the Tone Zone is VERY subjective to height, and the smallest of height adjustments can make a huge difference.
Also if you end up going with the Tone Zone, a lot of people like the Air Norton/Tone Zone combo, so look into the Air Norton S.
Just food for thought.