Right now your tier story around pricing is decent, but I think you could make it better. Free tier is fine, but at basic tier I think you should at least consider adding electricity costs. Then based on the data you have, identify a fixed median cost for things like print time and maybe labor cost.
The idea would be, let people like me have a better picture of what they’re actually saving when making something themselves, if anything. And if it’s someone trying to get a business off the ground, give them a rough idea of their costs even if it isn’t accurate enough for them specifically to be used for pricing.
Even though it’s not accurate, it helps them get started. And when they’re sufficiently established that won’t be good enough and Pro becomes a natural growth step so they can fine-tune those costs for actual pricing use. Meanwhile, for those of us who are just curious about the value proposition and ROI of our personal use it’s plenty accurate enough.