Thanks for the recommendation. It looks like a great service and I'd love to support them, but as a student I just can't justify $10/month as long as Google with an adblocker is still an okay experience. Credit card being the only payment option is another problem, since I (like most people where I live) only have a debit card, with credit cards usually costing extra. I'll definitely keep an eye on kagi though, hoping for more payment options and a <$5 subscription.
It depends on the kind of debit card apparently. What I have is a girocard[1], which doesn't have the required 16 digit card number and CVC. I didn't even know that debit cards can have those. My online payments are usually made via SEPA bank transfers, Giropay[2] or Paypal.