Those drives look HUGE, but actually look like they are the right scale.
Very kind of you to post all these images and updates.

Looking at the aerial image you posted earlier, there is a hot tub on the bow already, and the hot tub looking thing on the stern looks like it sits half a deck higher than the top of the jet drives. So it still might be possible to install the stern hot tub and make it look good. The whirlpool on the kit seems to be a bit tall, and the wood trim is definitely over scaled in width.



http://www.jcd-spotter.de/schiffe/Prime/prime.htm