Hello Mr. Delt,
I have viewed this video twice in its entirety.
I believe what you are hearing is a lack of dynamic range in the sampled piano. I am not kidding: You may wish to try reducing any of Pianoteq's models' dynamic range slider to a level between 10 and 15dB(!).
I was watching the rather light touch the musician was using in the video, yet the sampled piano sounded loud and full throughout the key range -- this is an indication that the sound was either highly compressed in post processing for the video, or the instrument has an extremely compressed dynamic range.
Regarding the various other presets, such as vocal and strings (yes, I know you didn't specifically refer to these sounds), they seem to come from Yamaha's Clavinova series of electronic pianos.
There is something I noticed in the video that you may or may not have caught: Look at how that piano is miked -- they look like cardioid microphones placed at right angles to each other and the two microphones' heads are nearly touching. I suspect they were placed over one of the electronic speakers positioned under the piano's soundboard. Please note there is a so-called "proximity effect" that is heard when cardioid microphones are placed rather close to the sound source -- it's rather similar to how one's recorded voice sounds when the microphone is almost touching the singer's lips ... the proximity effect does make things sound "deeper" than if the microphone has an omnidirectional pick-up pattern, and is positioned several feet to meters away from the sound source.
There is another factor that wasn't mentioned, namely a comparison in audio systems between the amplifiers and speakers in the Yamaha, versus the audio system you are listening to the audio portion of the video.
These are my initial thoughts. Rather than furnish you an fxp of my own design, I might suggest you start first with decreasing the dynamic range slider. In that way, you can get full sounding bass, and the higher overtones will become more present (but not much louder) when you play with higher finger pressure on your keyboard.
Cheers,
Joe
