Cost of Backups should be dependent on Storage size not on the size of Droplet. Because bigger Droplet can have small Hard Drive due to Digitalocean Flexible resize option. Consider I'm running $160 Droplet backup cost for this is $32 per month, this is ok if I'm using full Hard space provided on this plan. But if i'm running same plan which is resized from $5 to $160 using flexible resized option then hard drive space for that plan is only 20GB then backup pricing should be less because i'm using less hard drive space which will decrease snapshot size for bigger plan. So please decrease backup plan size if droplet is flexible resized from smaller plan and take only price for smaller plan pricing.