|You can't have enough John|
SimpleQuest is a small format, lighter iteration of OpenQuest. The biggest difference mechanically seems to be swapping out the original three magic systems with the unified MP-less One Magic System already introduced in the OpenQuest Companion, otherwise it mostly focuses on trimming down the rules, content, and stat blocks. I won't delve depper into the details about about the differences between the two games, because there is already a preview for a book and a comparison with OpenQuest on the Kickstarter page.
In several ways it seems to be closer to what OpenQuest 3e was intended to look like, before the author decided to stay truer to the roots for the anniversary. With Dragonbane and SimpleQuest in the pipeline, 2023 already promises to be a good year for fans of BRP and its derivatives.