If we used more than 5 Action Points in a round, perhaps something along the lines of 20 AP per round (at a minimum - i.e. where 1 AP = 1/4 second as it were), I could easily see Speed being used as a factor on total number of AP, or on the AP of actions.
However, the number of AP are so few, and the AP cost of Actions are so small, that trying to adjust them using Speed (Value or Bonus) would require implementing some large equations to figure out how they would reflect things, which means having to create a table for every possible Speed variation. There is no simple one-to-one correlation between any of the factors involved.
So, to give a short answer - no, I don't think speed should not have a direct affect on number of AP per round or the AP cost of thing.
Now, an alternative AP system does sound like it would make for an interesting option on down the road, and that could be interesting....