I'm aware, but it's if she had a simple interface already, as she said she has been having fun playing with the DJ controller/decks already, also she's had something up on Bandcamp/Soundcloud so I wasn't sure.
For connectivity for keys... you could go direct to PC, or via Midi on the NI (and Akai as well I think) but probably keep it simple with a USB > midi cable.
Something like this
I would also recommend looking into Akai MPC Touch and as you're new to this, MPC software is excellent, with great sample editing capabilities too. DAW integration has been introduced as well.
Akai MPC Touch
Otherwise for general interface and DAW integration the NI Maschine is a decent first choice, partly cause Komplete is partially included too.
Another contender if you want deep integration and enhanced workflow is Push (you'd have to get Ableton as well), and though it's more expensive when buying both the hardware and software, it's very versatile/powerful combo. (this one is good if you have an audio interface, as push has no analog i/o, just two pedal controller sockets)
About Push
Push Bundle Pricing With Ableton