Sunhokey Prusa I3 Modification for Smooth Filament Flow

So I experienced jumping extruder motor and clogged nozzle and upon investigation I noticed the teeth mark left by the extruder gear on the filament.

I suspect this was causing the problem so I tried to adjust the tension on the clamp of the extruder to avoid having teeth mark. But teeth marks still remains and did not solved the problem.

Now since I cannot eliminate the teeth mark, I focused on the passage where the filament goes thru. I noticed there are edges that could catch or rub o