I had an idea for the 2.5 health system, where the character you control can have another layer of 'hp'
Shields would regenerate somewhat fast, but health regenerates slowly
~Concept Maths
Say you have 250 health, 750 shields;
You become damaged by 875 points;
You are left with 125 health, 0 shields;
~Regeneration
After you were damaged, your health regenerates by ~1 point per 2 seconds;
Your shields regenerate by ~2 or 3 points per second
~~~
It is probably too much wonk (yes, wonk) to program, but I think it could work
(Te gusto con mi tensos condicionales y subjuntivos?)