If you are able to place it like in my video (it is on the edge of the MoXF, supported by the back part of the keyboard stand with a supporting specially cut styrofoam block underneath), you can reach the imporant live buttons for arranger functions easily enough, and the buttons are fairly big. Changing individual sounds however is difficult, you have to prepare sounds/sound changes at home, e.g. by preparing performance lists for the USB stick.
I tried the same backup with my kronos and the audya module... Just didnt feel right to me...
One of the reasons i ended up with a pa3x now.. ( with a 27" touchscreen and vsts where your bk7m is. The touchscreen is ideal for setting up sounds and such, but when real life playing, i just use the controlls of the Pa3x..
But then its a good thing we are all different, glad this works better for you, and as long as you are happy, you should stick with it