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OK I can see the graphs now (not sure why I couldn't before)
Straight away I can see it is motive force. First clue is that the Power and torque do not cross at 5252. Ignore your numbers and re-calcualtre the figures if it is that important to you. Look at the shape, a flat torqe curve that increases in the second half, that looks like the cam being advanced by the VVTi to me, exactly as it is it should. OK, so you have more torque up high... I bet this is how the motor was designed.
I have driven a Corolla sportivo (road car, which I think has the High performance version of the same motor) and the way I remember it was that you had to rev the tits of it you make it go, to me this graph is indicative of that. I will go back to what I said before, this will be the way the motor is designed!
Here are the realities of life, you don't get something for nothing with cams and NA motors (although VVTi and VTEC do the best they can through two completely different ways). More torque up high means more power, to the detriment of lower and mid range. To put it in to perspective you torque curve is better EVERYWHERE than the VW motor (which is known to have ports that are too large to the detriment of torque)… and the problem is…
Now if you do not like that and are going to modify you need to concentrate on increasing the efficiency at lower RPM, but that will cost at the top end (or more likely may not allow the maximum possible) this means increasing gas speed down low, maybe smaller headers that scavenge better, working on the valve seating so flow at lower lifts is better, that sort of thing
People who race want to keep as much high end torque as possible and we gear so that you do not fall off the curve
EDIT I just looked at our local spec for the Corolla Sortivo max torque is at 6800(!), and max power at 7800
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