Dreamer, what I do with my G1000, when used as a midi controller[a good one too]...I assign the parts that I want to use as my transmit channels..The G1000 has two midi outs that any parts[realtime ] and song parts [can be reassigned]..another method I do, is route the realtime part I don't want to hear, to a seperate out[not cabled to the mixer].
This is one of the capabilities I am concerned I may lose with the G70[Alex, I also have not played a G70]..

You can save a group of midi set ups that can be brought up seperate from the Performances[on the G1000 and probably the same with the G70]...most of my controller set ups reside in my User Performances[as an example my Native Instruments B4]..], I still have all the arranger features, color sounds from the G and the B4 at the touch of a button[192 on board selections, too]..
Time will tell if the G70 will/can replace my G1000...I'm sure I'll have a G70 soon[but may not replace my G1000]..
BTW, do you know that the G1000 can transmit 7 channels across the keyboard, with just a push of two buttons together..Realtime parts without reassigning channels.