Felix, GRG and Gregg give great advice. You can run both on the same track. I'm not a big fan of doing this unless you find two trains, one commend and one conventional that can play nice. A command unit needs at least 13 volts. (give or take) At 13 volts the conventional will be a rabbit so to speak.
Patternpilot, You can, but no need to keep moving wires. First, this all depends on how much you're running and how you power the TIU. If you power the TIU using the AUX You can just run power thru Variable 1 or 2 and just choose fixed or variable from the remote or tablet. Or without Aux power, you must run power to fixed 1. You can jump power from fixed 1 to Variable 1 or 2 simply by jumping wires (from the input side) from fixed 1 to either of the three remaining choices. This way, you must power the fixed 1 input, but you don't need to use the output from it.
