Back in the day, eXe was pretty okay and open source. I've heard it was picked back up for support a couple years back but didn't really follow it.
I've used Captivate, Camtasia and Lectora to develop SCORM--they are all authoring tools (though Camtasia is very video focused) that work relatively well. I'd recommend Lecotra above the other two but they all cost--and Lectora is the most expensive (also the most flexible--but it requires your brain be flexible, too). Some people really like Articulate products (I've never used their products but their community is amazing). Articulate is less expensive than Lectora and maybe (these days) Captivate, but likely more expensive than Camtasia. Camtasia is often an add of for other authoring products (I got it with both Captivate and Lectora). That's SCORM authoring.
Have you looked at the Lesson module? It is quite powerful. You can do so many interactive things with it. It is not especially pretty but VERY functional. That's the only SCORM selling point, in my book--they can be very pretty. Both Lesson and SCORM have crummy reporting.