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A second at a time is way too long for the trim adjustments. Try just flipping it for as short a time as your thumb can manage. It may take more than one adjustment, but keep the adjustments as short as you can.

My 2010 13' Whaler has a whale tail on it and I haven't experienced any of the issues the OP mentioned.

I've had good luck with the trim adjustment by putting the trim all the way down before I accelerate from an idle. As the boat is making the transition from displacement speed to planing speed you should be trimming up and pulling back on the throttle. Practice will tell you how much to trim up for the "first adjustment". After the boat gets up on plane then make very minor adjustments to the trim, trimming it up until the boat starts to porpoise. At that point you've gone too far so just flip the trim adjustment down a time or two to stop the porpoising.

Listen to the motor and watch your speed and rpm's. When you're properly trimmed the sound of the motor will smooth out, the rpm's will climb (without any further adjustment to the throttle) and the speed will pick up.

The sweet spot for trim adjustment will depend on your load, water conditions and your speed. You'll soon learn when it's right because the sound of the motor will tell you.