Product suggestion: DDJ-SX add-on controller

Dear Pioneer, please could you make one of these........

It's really easy to mess up switching between decks 1/3 and 2/4, so here is the answer!

I wouldn't use 4 decks often, but 3 would be really useful.  This add-on controller could be placed left or right of the DDJ-SX.

For 4 decks 2 of these could be placed on a stand over the DDJ-SX and selected as decks 1/2, with the SX providing 3/4, so the volume sliders are in positions corresponding to the decks.

Would obviously need a Serato update though.

If you make a fortune selling these then don't forget who suggested it!