Let me know if you want me to try some modifications like making this thicker (if this is where it broke). As long as someone is willing to do test prints I’m willing to work on mods. 
I tried breaking this tab off of one of the tests and there’s noooo way I’m going to break that off without a tool and some good force.
The side tabs might be a different story. The last test print I did had them fairly small, so I can break them off easily. It looks like the last change I did was make them larger to fix that very problem. But it’s possible I didn’t go far enough.
They are definitely thinner than the top tab because I was worried about having enough flexibility to pull the case off. But they might benefit from being wider or thicker (or both):
I have noticed when carrying the phone that those side tabs do allow a little bit of flexing of the side of the case. Not so much that it was concerning me, but this could be an area for improvement.
So if you meant the side tabs, I could see those being an issue. Top wide tab… that sounds like maybe some difference between printers or slicer to work out…