Hummingbird does not destroy OMAP, they perform within 1% of each other. You seem to forgetting(or are unaware) that both the Droid X and the Droid 2 outperform all Samsung Galaxy S phones in the Quadrant system benchmark. The PowerVR SGX 540 is faster than the enhanced SGX 530 in the 2, but it's a 10-20% difference in performance, nothing massive.
Liking or disliking Touchwiz is nothing but personal taste so having Touchwiz can be a pro or con depending on what the user likes.
You're also omitting the single largest difference between the two, which is the network. Verizon has an order of magnitude more high speed internet coverage than Sprint. It is difficult to find a place in the country where you get under 1mbps download speeds on Verizon, while some 90% of the country has 100kbps or less speeds on Sprint.
See the red? That's where you can get a bare minimum of 1mbps downloads on Verizon.
http://www.rentcell.com/images/verizon-coverage-map.jpg
See the orange? Those are the only places in the country where you can get 3G speeds on Sprint. Go outside the orange and you're down to 100kbps or less.
http://coverage.sprint.com/images/mapdatasprintUS.gif
Sprint's Wimax 4G is going to become obsolete in the short term as well. Sprint is using Wimax as a temporary gimmick while they set up LTE. It's nothing more than an attempt to slow down their severe subscriber bleeding while they push out the real 4G. Wimax phones like the Evo and Epic will be out of luck in the near future since neither of them support LTE, which Sprint is moving to.
As long as both devices are locked to these networks, the network the phones run on is a huge factor in the user experience created by these devices.
I think it's pretty clear that the Epic does not destroy the Droid 2.