Since you're wanting an arranger keyboard may I recommend the Tyros 5 (76-note version) which can split the arranger and keyboard functions into 6 - 8 different outputs. (Press "mixing console -> output" to access this complete output matrix menu.) You can split and send any section of the keyboard or arranger functions up to 6 mono or 3 stereo outputs (eg LH, RH, RH part 2, RH part 3, multi-pads, vocal harmonies, style bass, style drums, audio drums, whatever is needed).
I use the Tyros 5 this way in my facebook and YouTube live videos. It's a great tool to be able to separate the outputs and split the keyboard and separate the two hands, and even more so to send out separate arranger instruments and vocal harmonies.
Hope this helps.
Dr. Steve Kuban
PS: Here's an example: "Bridge Over Troubled Water."
Here are the output assigns I used:
Output 1 & 2 (stereo): arranger instruments (bass, drums, guitars) plus left hand;
Output 3 & 4 (stereo): right hand (playing the live piano)
Output 5 & 6: live ALTO vocal harmony to 5 (using the built-in vocal harmonizer)
live TENOR vocal harmony to 6
(I like sending the vocals out on separate outputs, it gives the ability to adjust the vocal harmony blend as needed.)
While singing live on facebook or YouTube, at the same time I output and record these 6 outputs to separate tracks of a multitrack recorder (eg. Zoom R24 8-track recorder, or DAW via an audio interface with discrete outputs, eg a Saffire Pro24DSP which has 16 simultaneous inputs, that's what I use).