I’ve been thinking about this as well and even considered moving my task system entirely into Obsidian, just as @ryanjamurphy did.
I was first inspired by the way Noteplan allowed for task filtering and then by the use of Obsidian’s Dataview plug-in. (Evernote’s implementation looks a lot like what Noteplan has with its review filter, so I don’t feel like this message is hijacking the post topic)
While the experience of trying was actually very enjoyable for those same reasons Ryan pointed out, it did not stick and I reverted back to my Things setup with links back to the corresponding Obsidian notes.
The main reason was the lack of fluidity on task filtering and the whole process of tagging and processing that was built into Things and I took for granted since using it from v1.
That said, one of the things that I brought back with me into Things was the habit of using more the note field to capture details of the decision making involved in the action and into the project itself.
That is definitely not ideal, mainly because of this:
That was really something to have. But it didn’t last long with me as I deeply missed how projects, tags and statuses (today, scheduled, anytime, someday) are laid into Things and how easy it was to navigate it.
Having tasted that I even tried the filters and even Ryan’s (awesome) Review plugin, but in the end I found out the filtering and processing of Things indispensable to my workflow.