Your current pricing model is fine. If someone needs GitLab, they'll pay for it. If they don't pay for it, they don't need it. $30-60/year is cheap, even for a hobbyist project.
I think you may have validated what the OP was saying :-) It's $3.25 per user per month, but the minimum order is 10 users. So the minimum price is $390 per year.
We aren't hobbyists, we are just a small company 5+-1.
And sometimes we hire people for a small amount of time, which could exceed 10. So for that time we would need to have a bigger license?!
If you exceed 10 non-blocked users you would need a bigger license. If you can block certain users at certain times you would be able to use 1 user pack (the users are not named).