userb you will have to inquire to Imgur if you have questions about their terms of use.
This extensions uses Imgur's default API, and I think you can use either a free or pro API key with it.
If you want to send files to an unsupported endpoint, you could create your own adapter and connect it via the local extend.php. This will require a bit of digging since we're lacking documentation on how to create additional adapters, but the code was made to accept customer-provided adapters.
