Does it suck for the average gamer? Well, we will have to wait for actual reviews, but, the bang for the buck doesn't appear to be there, unless you do those bundles.
Vega 56 at $400 and 210W TDP (and going by recent AMD offerings, about 90-95% of Vega 64) sounds like an excellent deal. It reminds me of R9 290. I expect good overclocks as well, getting the card to stock Vega 64 performance levels.
If it also supports HDMI 2.1 (and variable refresh rates, same as Display port adaptive sync), it'll be the card to get for many gamers. Though this feature is more likely to debut with Navi.