[Feature request] two hold state flavors for hold-taps

[Intuos5]

As of the time I am writing this, Hold taps have flavors for how to deal with keypresses during the tapping-term-ms, but they do not yet have a way to deal with other keypresses when the tapping term has already expired. I therefore would like to request a holding-release-flavor. This holding-release-flavor has two states: first, when the tapping-term-ms is expired and no other key was pressed before releasing the hold_tap: and second, when the tapping-term-ms is expired and other keys were pressed before releasing the hold_tap. In the latter case, the behavior of the key changes.

Idea
This could be useful in conjunction with layer changes. The holding-release-flavor allows for merging &mo and &to(g) hold behaviors to a single key, hereby referred to as &moto or &motog. It is different than an &mo &to(g) hold tap, because the tapping behavior of the key can be set to any other behaviour, leading to a three state behavior.

Use case
Hold_taps are a great way to double up key usage in a layout, I therefore use hold_taps for my layer switching needs together with Home Row Mods. I use the shift key positions in regular QWERTY keyboards as hold_tap layer switch, together with TAB and Enter respectively. However, doing so only really allows me to choose between an momentary layer (&mo) or a full layer switch (&to or &tog) if I want to be explicit in switching and timerless (i.e. no sticky layer) for multiple keystrokes.

Example
An example of such behavior is switching to a numpad layer.

1. If you hold the &motog key and release it without having been interrupted by other keypresses, the &motog toggles on the numpad layer. This means you can input longer sequences and can use the pinky key with homerow shift. For example, with CAD modelling, you might want to input formulas, enter values for in multiple input boxes seperated by TAB or cells in a spreadsheet editor.
2. If you hold the &motog key and subsequently press other keys, you can input number keys. Releasing the &motog key then switches back to the previous layer, which is helpful to avoid having to press another key to toggle. Especially for short numeric sequences (e.g. a couple digit long numbers) this negates a relatively high percentage of key presses to toggle back.