abilities

Like kevoq said, it really depends on how you use him and how many AP you have to spare. Here are the combinations I'd consider based on his discounts:

Short In Elite (1 AP)
This is the best ability for getting separation against man coverage. If you face a ton of man coverage and like passing to your HB on various stock routes, in routes, out routes, and option routes, this is the best way to go if you just want to spend 1 AP.

Short In Elite + RB Apprentice (2 AP total)
Everything I said about the first option, but four additional hot routes. Really though, the best one is the Texas (angle) route. It beats everything.

Grab-N-Go (0 AP)
If you don't have AP to spare, just go with Grab-N-Go for free. I don't think it's that great (on next-gen at least), but it's free so why not?

RB Apprentice + Grab-N-Go (1 AP)
If you really value the Texas route and you don't feel you need Short In Elite for the extra separation, get Grab-N-Go instead of Short In Elite and save 1 AP.

If you don't pass to the HB regularly in your offense, your best move is to just go with Grab-N-Go for free and spend AP elsewhere. If you don't pass to him, you also should consider selling Faulk and picking up someone else.

I hope this helps!