The D3 is a heavily CS'ed chassis. I'm not sure you would find it either easy to drift or even learn on. Some folk would say to learn CS from the beginning, and there's a lot of opinion about this, but I would counsel to start with 50/50, get proficient with that, then move on to CS. I went seven years before even considering a CS'ed chassis, and just CS'ed one of my 50/50 chassis (Tamiya VDF), only recently. The D3 is also needlessly complicated, and not a very good choice for a novice.

As far as recommendations for an "advanced" chassis, that's up to you. I won't make any recommendations, aside from telling you to make the decision whether you are going with a belt drive, or shaft drive, but be aware...."advanced" shaft drives are VERY few, and parts to CS them are even more rare. The only one I know of currently, that can be CS'ed easily, is the Tamiya TB03, and that chassis will cost a MINT to do so.
Belt drives are much more prevalent, and easier to CS, but you will have to restrict your drifting to smooth, clean areas, and by their design, belt drives require much more attention to adjustments and maintenance cycles.

If you do your shopping primarily online, you can get just about anything you want, that's within your budget, and there are some good choices, most from Tamiya, that you can start with, that won't cost much, but be ready to shell out at the VERY LEAST, $400, for the chassis and attendant electronics (aside from the power system, which you say you want to re-use).

On the power system - you would be well advised to stay with something close to a 17.5T brushless, or 17T brushed. Anything faster than those will make drifting harder, and the faster it is, the more difficult drifting will be. Smoothness is what you are after, and the lower-RPM systems are the smoothest. I, myself run nothing faster than a 13.5T system, and that is in a chassis that is dual-purpose drift and gymkhana.