Our team recently did some math on “the value of a dollar” for various tiers taking in consideration platform and processing fees. While this is nit-picking, this shows the overall efficiency of your tiers if you want to focus on using as much of your patrons’ efforts towards you and less towards fees. This was based on Stripe direct deposit and we’re based in the US:
Assuming US, using Stripe direct deposits and a Pro/Legacy plan.

Does not include Stripe deposit fee of 25 cents.
Tier value, less the -proc (Processing Per Pledge, less the -plat (Platform Cut) equals the value of $1. Please note, the platform share may vary and may look different depending on how many patrons you have. The goal of this was to give a general idea of “what is a dollar on Patreon worth depending on the tier we set up?”
The efficiency curve starts to flatten higher up and naturally higher tiers are going to mean higher dollar efficiency, but the numbers taught us that if we really wanted to efficiently price a tier it should start at $5. I know the $2 tier dollar efficiency seems high, but it (1) gives your patrons a reason to not support you for a higher amount; and (2) doesn’t allow you to actually contribute back effectively unless it’s a “general thanks” tier.
If you find stuff like this helpful I may make a public calculator to help you determine the efficiency better based on custom values to help with making decisions on tiers and rewards. I know to many this looks like penny pinching but let’s put it in perspective: If you want to give all Patreons of a tier a monthly postcard reward, you should truly know the value of their pledge to get a proper comparison to the cost because using $1 tiers to send $1 postcards may looks like a break-even but really it’s operating at a loss.
TLDR; if you want a nominal “general support no rewards” tier, make it precisely $2 and don’t give it rewards that cost time and money or you’re running at a loss. Any reward-bearing tier, consider time and costs but start at least with $5.