There’s a limitation, in place right now, regarding saving patches and including the aux and bus routings. Logic’s own default patches have this functionality but the end user is restricted in this area.
One workaround is to pack everything into a summing Track Stack but this is not always so elegant and includes unnecessary routings.

Here’s an alternative method:

1. Create an audio or software instrument channel strip and create one or many bus routings to use with your favorite effects.

2. Create tracks for the aux channel strips and make a summing stack of them. The easiest way to do this is to select the tracks you want to bundle then from the mixers’s local menu choose Create Track Stack for Selected Channel Strips or assign your own key command. A small drop-down window appears asking you to select the kind of stack you want. Choose Summing Stack.

3. Open the MIDI environment and locate the original channel strip. Drag and drop it over the Sum track then delete the redundant duplicate track inside the stack…