But you are reducing drag by reducing AOA
We're close, Pace, but still not there. As I've said, Vyse is not exactley minimum drag speed, but it is towards the bottom of the drag curve. Fly at any speed other than minimum drag speed and drag INCREASES.
Answer me these questions:-
Do you agree that a particular aircraft at a particular weight has ONE SPEED where it produces minimum TOTAL DRAG (that is, the sum of ALL types OF DRAG?) (and if you're not sure, have another look at the link I provided)
Do you agree that flying at ANY other speed increases drag?
Do you agree that said aircraft has ONE best rate of climb, single engine speed?
Do you agree that if the aircraft will only just maintain level at that speed, that it can't maintain level at any other speed?
The reason your aircraft will fly faster level than in climb is not because it produces less drag. Does your Seneca at 200kts produce less drag than when you are climbing it, two engine, at 150kts? If not, wouldn't it climb better at 200kts? But it doesn't, does it?
It flys faster because the excess thrust that was being used to produce the climb is now being used in level flight.
One misunderstanding you are demonstrating is the idea that you need more lift to climb. In unaccelerated flight, Lift=weight, and that goes for climb too. If lift is more than weight, you will accelerate vertically, that is "Pull G", and I'd think you would agree that a normal climb is a 1 G manoeuvre. Grab a PPL text book and have a look at the force vectors in level, climb and descent, and you'll see what I mean. A particular angle of attack produces a particular speed, whether climbing, level or descending.
What you advocate in the last sentence would work, PROVIDED you WERE able to climb at Vyse, even if only at a small rate. But if you can only maintain level at Vyse, by definition you will descend at any other speed.
And please don't bandy around kinetic energy. Aircraft fly because of the airflow over their wings and the speed and angle at which that happens. If you have more airflow, you can, in the short term, turn that into an increase in lift and a vertical acceleration, but that's aerodynamics, not grade school physics.
Next you'll be warning about down-wind turns and speed-loss due to momentum, but I KNOW you know better than that!!