I ran The Micro-RPG Jam last year (https://itch.io/jam/micro-rpg-jam) and I just wanted to say that a lot of the tools itch.io had in place made it very easy to run!
There was only one feature the site was missing that would have made things easier: a formal way to take a poll of jam participants on the community forum!
Without this, I had to use an outside polling service (Google forms) which not only took people away from the site but was also confusing for some members of the jam.
As game jams continue to grow on itch.io, I think it would be useful to have a basic polling system in place, so that game jams can have their participants cast votes on themes, help make decisions about the jam, or just give general feedback.