If, and that's a big 'if', the system was to be taken in that direction(individual resistances for each effect), a much better way to handle and track them would be the approach used in Dark Souls, and other Souls games.
The character has a tolerance for, rather than resistance against the effects: rather than tracking all the 'types of HP', and applying the effects once they are depleted, only the relevant ones are tracked, and they fill from zero to <tolerance>.
To become Poisoned, a character must receive <tolerance> amount of poison damage.
To become Frozen, a character must receive <tolerance> amount of ice damage.
Etc.
This approach however, is best suited for real time games.
A turn based game, with AP and other mechanics, has the design space to make more interesting effects, over making the boring ones easier to mitigate.
That's actually not a bad way to handle it. It still begs the question as to why you would do it, but certainly one of the more elegant solutions.
