Whats the general consensus on building a new Vega rig @ todays rates? (Card price vs earnings)
Yes no wait never

Never say never, but currently IMO price/hashrate ratio isn't in favour of vega. RX 470/480/570/580 gives better results.
You cant be serious? ETH profitability has been about as badish for months, dropping rapidly after june 13. Monero instead is still the best for gpu mining. Even if you would need to pay 500 per V56 versus 300 to RX580. You can make a dollar per RX580 in a day (120W) versus vega +2,5$ per day (150W).