I completely agree that the rate tiers and API request charges are complications that are best avoided.
That said, ease of understanding to me correlates highly with how intuitive and easily-to-anticipate something is. Much of the allure of cloud services is the idea that an individual user pays only for the services they use, and the service provider can offer low incremental rates by aggregating many users' usage.
Finding the maximum-usage clause in the DreamObjects fine print was unexpected to me because it does not seem fair to advertise DO as a cloud service. DreamHost is effectively selling remote disk space in a traditional $/GB model, with the only difference being that the plan size adjusts automatically each month.
A flat rate on GB-hours (advertised as GB-months) would be extremely intuitive: your stuff costs money while it's on DH's servers, and doesn't while it's not. If you store a file for half a month - it costs you half as much! Replace a file with a same-sized file in the middle of the month, maybe with an hour or two overlap, and you'd get charged for the same space as one file being there the whole time. If someone doesn't understand GB-hours, just say they'll be billed for average usage - with hourly or even daily quota calculations, the difference is negligible.
I completely understand that the current billing model makes it easier for DH to predict storage needs, but I have a problem with it for two reasons: 1) It's very different from what your biggest competitor does, even though you compare yourselves with them as though it's apples-to-apples; and 2) I liked you guys back when I was on shared hosting here, and would love to become a customer again, but for my current backup workload, I'd be charged quite a lot for the brief period where two backup archives exist on rotation; compared to RRS + Glacier, the promo rate is comparable, but your standard rate doesn't even compete.