There’s people here every week disappointed that they purchased a 2-3 years cheap subscription and ended up locked because their VPN was compromised, went down in performance or discontinued their favorite server/feature.
Mullvad ethical pricing is actually one of its greatest strengths. They don’t overcharge the monthly fee and allow you to keep it flexible. You also get 10% discount on bitcoin payment.
That said, if it’s really that expensive for you, check out cryptostorm or AirVPN. But they’re not as beginner-friendly as Mullvad.
I think cryptostorm is best bang for the buck. But if you’re not a techie I would recommend Mullvad instead. AirVPN is good but I dislike the overkill clusterfuck of their website and app.