You seem to be describing skank (or upstrumming if you're on guitar). Your example however (Guettastep) is not skank'd, it's 3 syncopated notes followed by 8th notes.

The pattern if you think of in terms of a step sequencer I believe would be:
1, 4, 7, 11, 13, 15

This doesn't really answer your specific question, but I think it would be a lot less convoluted to use an audio effects rack to do this kind of processing. 3 chains, frequency split each chain, and process away. Then you just have a single channel when you want to bounce out your finished product.

Shitty turntables will drive you insane. There's a reason people always jump on these threads and suggest to not buy anything other then tech 12's. I'm among the many who ignored that advice when I first started and got some Numark tables. Not even the bottom end models, but some mid-priced, direct ...

There are tons of websites that help with scales/chords without learning the ins and outs of music theory. If you want a crutch just google "scale finder" or something like that. Find a few notes you like the sound of and plug them into the web app and it spits out all the scales that use ...

M-Audio Axiom 25 is kind of in the upper of your range but should also be considered. I love that it has 8 knobs & pads on a 25 key, making it more well rounded then the Oxygen.

You mentioned your using traktor. You should be able to rewire each of the decks to another DAW like Ableton Live. Each deck then gets recorded into a separate channel (as a wav) and you can master your mix before flattening. I haven't done this myself, but I am pretty sure it's do-able. Quick googl...

Look for used Vinyl too if you do decide to go that route. If you have some local scene forums you can usually hit those up and see if anyone is selling off their vinyl. It will help you get a decent starter collection going. Mixing 5 records over and over gets old really quick.

Entry level turntables are a different beast then entry level CD/Midi gear. The problem with low end turntables is that they don't have precise / powerful drives (entry level stuff is often belt driven). This means that even if your beat matching is pixel perfect, the turntable may tend to slightly ...