Before this get's any uglier, I'm goin to answer your questions.
No, your imdence won't drop any lower. Impedence changes with frequency and power applied, but when speaker manf. rate impedence, they rate it at the lowest possible value. If not, then a person could potentially blow a amp by running it too low on accident, if a 2ohm sub could drop to .25, but your amp is stable at 2 at lowest, you'd be in trouble. There is a reason it's called impedence RISE, it increases, not decreases.
Secondly, you had a comment about smaller boxes having lower power handling, this is untrue. There are 2 main types of power handling, mechanical and thermal. Mechanical power handling is how much power it will take at a given frequency to drive speaker to it's maximum excursion. The size of the box dictates this, smaller boxes require more power to reach maximum excursion due to the increased pressure on the cone. Hence, larger boxes have LESS mechanical power handling. Thermal power handling, on the other hand is simply how much power it takes to fry the coils. All and all, this is pretty much the same in any box, as heat dissapation is more a product of coil surface area than anything else. SPl competitors use this to their advantage. Ported boxes dont' allow for much movement near tuning, so high power handling is a must. It takes alot of power to make the cone move at all near those frequencies, plus they are burping a higher frequency where excursion isn't an issue, so thermal power handling becomes the true limiter.