I think it might be better to have 2 cards, as stupid as it may sound.
One for lower deposits ( Wirex, Cryptopay ) and one for bigger deposits ( Bitstamp ). Wirex or such for low deposits, like 50 EUR or something where it won't matter that much if you get 50 or 49 EUR on your actual card, and Bitstamp for deposits over 1000$, as it's more convenient to pay 2% upfront at spot price and be done with it. Reason I don't recommend Bitstamp at lower deposits under 1000$ you get charged 10$ per deposit. If you want to deposit 50$, you actually get to deposit 40$, which is significantly lower than what you'd get using Wirex or Cryptopay.
Complicated stuff, man. If only Bitstamp would lower fees for smaller deposits, it'd be pretty damn perfect.