I know this is not priority and trackers themselves may be deprecated by DHT,
but in the mean time a better lay-out for those screens could help, with arrangeable and sortable columns, like in Transfers.

A simple way to achieve that would be a column on the transfers list (with a simple check box, maybe) to enable/disable channel sharing of each file.

As I share what is in transfers, it would be even easier just to associate each category with a channel (or a few channels).

Without that feature the DHT itself would be a "master channel" and the point of channels becomes less evident, or at least less people will feel motivated to use them.