I'm just a customer. I like that Itch has DRM free options for games. I like that the Itch client is FOSS. I like that the store pages give the option to list details such as the engine used. I like that I can download the game files stand alone without using a client.
I wish that the notifications for game updates were easier to find. For example on GOG when I look at my game list for games I own it tells me which ones have had updates since I last downloaded the files. I also wish that Itch would do a better job moderating developers that falsely advertise their game. For instance some list a Linux version but when I go to download the game it only has a Windows version and even after reporting this the game is still for sale advertising a Linux version. Lastly I wish that reviews were public for all not just developers and those who follow me.