I agree, the whole setup is perhaps an overkill for mere gaming, unless you want a good setup and also happen to use it for gaming.
What I can say from experience is that the D3020 is a superb desktop amp, due to its compact form factor/footprint and digital connectors. I experimented with it hooking up a PS4 via optical and it sounded great with B&W 685 s2's for gaming (although again, it is 'overkill' for gaming alone). I find the D3020 able to drive almost any speaker I hooked up to it within reason, however, it does not do miracles, and in large rooms you'll easily reach its distortion limits.
The D3020 also works great if you add a passive sub. Maybe get less expensive speakers and an active sub if you want to game with this type of setup?