F1 custom qml script

No.

But you can fully MIDI map it. It's got MIDI mode (SHIFT+BROWSE Button). You can configure the MIDI format and colours with the Controller Editor App and use a generic MIDI tsi file in the Controller Manager to add assignments.

You can also edit (and overmap) the default F1 mapping (for Remix Deck and Stem Deck) if you want only to add/override the original functions.

You can also replace it (or use along-side the default mapping) with a user-mapping that works much like the default mapping except it has zero default functions. In the F1 panel you can set the SHIFT+BROWSE function to switch between default and user mapping instead of the default and generic MIDI mapping tsi.

To your first point. F1 is just right for Remix Decks. It has a few functions not accessible in any other way, not even via GUI or qml commands. One of them is non-quantized adjustment of the beatgrid (called nudge) which is great for remix set prep. And you can adjust sample gain with SHIFT+Fader. Read the manual for more details, and look for the excellent videos by Native Instrument for a visual overview of all of the F1's functions. Also, the F1 is dead cheap second hand. And there are a ton of excellent mappings out since the device has been on the market for such a long time.

😊