I did a small test and this is what I found. I’m running the most recent build that @alphacactus posted in this thread. Teletype 3.0.0 267A22F
Scene 6
I:
G.BTN 1 0 0 8 8 0 3 1
SCENE 7
Scene 7
1:
IF EQ 1 G.BTN.V 1: TR.P 1
If scene 6 is loaded from the keyboard (ESC, [] to Scene 6, ENTER), then the button displays but SCENE 7 is not loaded. This is the same behavior if scene 6 is loaded from the grid ops controller.
If after loading scene 6, the INIT script is re-run by pressing F10, then it proceeds to scene 7. The grid ops button remains intact and triggers script 1 in scene 7. Same is true if you run INIT manually from grid integration.
Finally if you change it so that SCENE is called from a numbered trigger script instead of INIT:
Scene 6
I:
G.BTN 1 0 0 8 8 0 3 1
SCRIPT 1
1:
SCENE 7
then calling scene 6 from the keyboard or grid integration proceeds to scene 7 with the button intact, and firing scene 7 script 1.
I’m not sure if it’s expected behavior that calling a SCENE op from INIT doesn’t do anything or not… I mean it does but only if the script is run manually and not as part of scene load.
But yeah, using this technique, you could theoretically have at least 9 scripts for set up kinds of things, leaving all the scripts in a called scene open for reacting to events. Possibly you could get even more scenes of set up but you’d have to trigger the 2nd set up scene’s INIT manually with an F key or grid integration, I think, since a scene called with an OP won’t run INIT automatically.
I hadn’t thought of but do really like your use case where a single scene sets up a consistent set of grid objects, then you can call many possible other scenes to have the familiar objects do different things. 
EDIT: Kind of a caution here though - I think in the final config, I have blocked myself from ever editing Script 6 which may be why it doesn’t load the scene when INIT is run at scene load. Probably need to read the parameter knob to evaluate whether you want to edit or proceed to the next script.