Controlling animation presets programmatically
Yes, that's perfectly possible, though it might be more work than just doing the animation yourself. 

You'll have to find all of the changes that the presets apply to the layer and adapt them with expressions that respond to the value of the slider. To find all of the changed properties of a layer use uu (double tap the u key). You'll have to apply preset 1, find all of the changes it makes, and write an expression that mimics them, then revert the layer and apply preset 2 and do the same thing. Then in your expression for each changed property you'd have:

var ctrl = effect("Slider Control")("Slider");
if (ctrl === 0){
    value; //use the current value of the property
} else if( ctrl === 1){
    // the expression that mimics preset 1
} else {
    // the expression that mimics preset2
}