Are you sure you have mites? That doesnt look like insect damage to me. Dont treat a problem until you are sure it IS a problem and you can confidently identify specifically what it is.
I think you are trying too hard. Let the plant grow and establish itself before you start pruning. You really want to let it grow up so you can see where the most productive points will be. I dont prune until a couple weeks into flowering, after the stretch.
The leaves are fine. The curling is normal, the leaves dont have enough room to stretch out yet.