Alternative Health Methods

As you push gently on the mossy wooden door, the smell of strange concoctions and pickled animal parts assault your... whoops, wrong opener. Important details: In this semi-turnbased game, there is only one playable character. She was human, but, after an accidental transformation, ended up half-plant. Over the course of the game, she has to reconcile her leafy green side, which "takes over" her human bits very, very slowly. At no point in the game is she fully one or the other, but initially she's very human and at endgame is approximately half-and-half. The plant side of her makes her resilient, but slower. My policy (at least here) is that the game mechanics should fit the story and the characters, not the other way around. Originally I was considering a regular health bar, where the player dies once the bar was depleted, but it didn't fit the character. Since she's a balance of two halves, I'm seeing if it would work to have a health bar that you have to balance in the middle - if she gets too human, she dies; if she gets too green, she dies. Here's how it works:

0     human      50      plant     100
|--------------*--|------------------|

Every time she has a human experience, like getting hit (bleeding, bruising), eating, or talking, take away points. A light hit might be -5, a full-course meal might be -25. Every time she has a "plant" experience, like planting something, having a plant reach another growth stage, or (I really don't want to program this one) standing still for extended periods of time, add points. Since plant experiences happen less often, they have higher point values: planting something new might be +15, while a growth stage might be +10. Her current position on the scale is marked by the asterix, so she's at about 45 right now. If you're wondering how she heals, first you must know that successful hits (from enemies) cut her - she plants seeds in the cuts, which doesn't necessarily heal her, it just adds points. However, she does have a maximum number of open wounds, so in a sense it does heal her. The challenge in a traditional RPG is to keep your health bar as high as possible. The challenge here is to keep it perfectly balanced at 50. Perfect balance awards you bonuses (double attack, extra items, another turn), while getting too low or too high has penalties - if you were at 10, for example, which is far too human for this character, you would be extremely weak. Most of your punch-kick moves would be available to you, but your plant-based abilties would be limited or blocked, and your natural defense would be next to nothing. At 95, your defense would be very high, but you would be unable to move except for a couple very limited plant-based moves. Should you hit either 0 or 100, you're dead. Questions: -What potential issues do you see with this system? -Other than health bars, what other forms of health tracking have you seen? Did they work? Disclaimer: I have no intentions of making money off of this game, so I don't give a hoot about the market or what sells in the game industry. Give me your opinions based on you, not "them."