dragging while starting from full stop

The first, easiest thing to check for would be brake calipers that need lubrication. They can literally be making your brakes drag against the rotors. Like someone else said recently, when you jack up a wheel and give it a good push it should spin freely for one or one and a half revolutions

 

Real stupid stuff: parking brake's off?

Any recent brake work, especially the rears? They can drag if not put together just right, and it's too easy to screw up.

 

if power mode actually works okay, then you have a bad go pedal or ecu. but try flooring it in eco or normal to be sure.
more likely the early pedal power is fooling your senses

 

I would chocked the front wheels, jack up the rear, set it on safety stands, apply/release the parking brake a few times, then try spinning the wheels. With a good push they should go at least a revolution when you let go, even two. There is a slight amount of inherent drag, due to the disk brake design.

But, if they really fight, stop as soon as you let go, you've very likely got misaligned caliper piston. When reassembling you have to orient the piston thus:



There is a stubby pin on the back of each rear brake pad, and the pin on the caliper side has to be between the raised "spokes" (shaded area) on the face of the piston. And it needs to be well seated thus. You want to assemble the brakes thus, and ensure everything is well seated, depress the brake pedal multiple times. Don't use the parking brake yet. Then take the car for a short test drive, going easy on the brake, and when getting back, apply/release the parking brake a few times.

Then, raise the rear, again, redo the spin test, to verify everything's still ok, the caliper piston hasn't rotated, a pin rode up onto the spoke. If this has happened, you'll have a lot of drag, all the time, and in a few months will be looking at scored/rusty rotors, bevelled-wear pads.

Attached is the Repair Manual instruction for brakes.