interesting list, and good post.
I guess i'll respond with my own recommendations.
if your main sole reason of djing, is to skratch.
I suggest..
Vestax PDX turntable, and a Rane 56. You don't need to get two turntables, if your just planning on skratching. The PDX, has the ultra pitch ,and as a skratch dj, I can personally tell you, the ultra pitched helped me a lot. By slowing down the speed of the turntable, you'll be able to control the record much better, hence better hand control on your skratching. ( another turntable recommendation for skratching is the TTX-1 )
The Rane 56 is industry standard when it comes to skratching, I haven't kut with any other mixer thats a better mixer, other than the Rane *56 ( 57 with a serato ). Ive gone thru a lot of mixers, vestax, gemini, numarks, radio shack mixers and tascam. Non came close to the rane 56. If your a Dj on a budget, try to look for a Tascam xs-4 or xs-8, the only thing is, they're rare to find. Tascams are great because of their durability, and the quality of the fader. I've owned a tascam for over 4 years, and the fader hasn't bled. And I really beat the ish out of that mixer, bringing it to gigs, clubs, practices and sessions.
If you want to push your musicality with turntables, i suggest using the Controller One turntable. The Controller One is developed by Ricci Rucker, and Dstyles. A very innovative turntable, consisting with turntable notation. A very helpful tool, for both your producer minded djs, and as well as turntablist.
If your main goal is JUST to MIX, Techs are fine, no matter if they're used or not. As long as they run, they're fine. They're industry standards, and if you dj in clubs, 99.8% of them will have techs in their club.
I think Infect was on point about the belt drives. If your a BEGINNER, and if your on the fence about djing. Then belt drives, or "Dj in a box" systems are fine. As far as the start ups, I suggest not using the rubber mats provided with the turntable. Just use a slipmat, or some butter rugs. I've used belt drives when I first started out, and it served it's purpose as a beginner set up. You can buy second hand techs as well, if you like, but it's all about pricing, and the different deals you run in to. It's all up to you.
You don't have to be rich to have these things, you just got to be wise when you purchase it.