Thanks for your positive feedback LindaHamilton32.
My idea just seemed to fall into place after considering where such scene could have fitted in to T3 as we know it. I couldn’t think of any other way to have Sarah in the film other than have her housebound. If she wasn’t then the second half of the movie would more or less be the same as T2. Having Sarah housebound adds a unique depth and twist. Here would be a woman who wanted to guard her son all her life, but due to illness (could well be cancer) she is restricted. The frustration this causes Sarah to have would be interesting to see. The emotion on John’s face as he witnesses his mother still trying to fight, but can no longer fight the same battle, only one of her own would be upsetting to see. This fits nicely to the John we see in T3.
Having Sarah sacrifice herself would be the only way to go I think. After all, she’s already at death’s door. Not only that I thought it kind of resembled what we see throughout the Terminator movies; the sacrifice of others to help those who must be protected.
When the T-X emerges from the flames I thought of the T-100 walking out of the flames after the truck it was driving blows up. Maybe the T-X could have run out the house giving it that more menacing feel.
Not only do I think this scene would have had an big emotional impact it would have bonded John and Kate later on in the movie as after the death of both their parents they now only have each other, making the sense of all things lost even greater for them.