Well, the thing is with service teams they need to ensure they meet the requirements of the client, the freelancer whilst it being convenient and easy for them to manage commissions professionally, which is why it is very difficult to come up with original ideas that can work for all three parties.Yup! I think Discord has a limit of 500 channels per server so it would quickly be in a state that new clients would be in a queue, but this is also the case with ticket systems, since they are just channels.
For me my volume is much lower so I wouldn't hit this threshold, but for larger service teams I think they would need the ability to set a limit to the number of channels automatically created the "maximum private channels" as I wrote above. I think this is the case with ticketing systems in general that you can set a limit to the max number that can be active at once.
