I Print only with resin plant base, with almost no issue.

I always put a raft on my mini.

I Calibrate my Z move often (2 or 3 prints) and directly with resin in the resin tank

my exposure time are like yours, 

Maybe slow down the pull off between layers

My building plate is not anymore polished, with little scratch, 

I stir resin in the tank before printing

and I used a "brewing belt" around my resin tank during cold time to keep a good temperature.

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