I'm trying to determine pricing for a SaaS I'm working on. It involves sending surveys so I plan to base most/all of my pricing around that. I'm now considering using tiered volume based pricing, i.e. 100 surveys = $/9mo, 1000 surveys = $29/mo, 10000+ surveys = $69/mo (random numbers for now). This will save me from having to piece out a bunch of random features and check them all over (You have 3 teammates you can't add any more, you can only create one more Project, and you haven't unlocked super secret mode on this teir, etc.). I just count each survey and charge them the appropriate amount at the end of the month.
However, I don't think I see this option discussed very much. Is there something wrong with this method? Do users prefer standard tiers?