I have been a user of Aseprite for over a year now and I love it. It is the best piece of pixelart-creation software I have ever used and I am really looking forward to the new tile-editing system.
While doing some tile editing, I realized another feature that I think others would find useful as well: the option to make the preview window isolate what is selected. In addition to this, giving the preview window separate options for tiled mode would be helpful (eg. tiled in x, y, both).
I hope the devs consider this feature, as I think it would really enhance the workflow of tileset creators. Thanks for reading.