I understand you are not investing customer's money unless in government bonds. I can see you already open you APIs(awesome!) which comes with extra costs. Etc...
Overall I think I get why BUNQ is more expensive.
Still I am frustrated with the range of available pricings. I feel unfair to pay 8€/month if I don't need 25 accounts and 2 credit cards.
I hope you will reconsider it.