Mashing is out, regardless of the foot angle. You want to teach your feet to follow the arc of the crank with a supple spinning action.
Regarding foot angle, some spin toes down, some keep a level foot and some drop the heel at the bottom of the stroke. Some even change their foot angle with the load and terrain. I used to be a mashy toe-pointer when I used toeclips with sneakers. That was just my way of keepng my feet in the clips and on the pedals. When I got cycling shoes with cleats, and my flexibility improved, the foot became level, and when I'm climbing steep hills and the cadence drops, the heels drop lower.
You may need to work on flexibility and suppleness before you feel comfortable changing the foot angle. Concentrate on the arc of the cranks.
