Hello again! Michael O'Kane (@[borrado]) and I have been hard at work trying to come up with solutions for chunky outlines on spine characters in Unity and I think we've cracked it! Our solution uses a custom shader and requires art to be created in a specific way. We've both written brief documents explaining the process from our own perspectives.
Michael's technical breakdown can be found here:
https://flaxenflash.wordpress.com/2017/02/18/2d-outlines-in-unity/
My art process can be found here:
https://docs.google.com/presentation/d/13LhOiCibxRq8RFPpE25Q6eX91-x0CdjAFLuHtghoMfg/edit?usp=sharing
Let us know if you find this useful or if you have any questions. Setting up the art is a little bit complicated and I don't think I did a great job presenting the information. Hopefully you can figure it out from my ramblings!
Keep up the good work everybody!