1, 2 and 3. Pruning.

This is a lower sprout. Upper ones are much more advanced.

What would you do here. Cut 1, 2, 3, or none at all?

Is it OK to wack an entire stem if it doesn't look very promising?

How about cutting some out to make room for award winning growth?

I've heard that you're not supposed to do any pruning after you start flowering. True?

Much thanks.

I would say cut 1 and 2, probably 3, if you have a different angle. That said I'm super new to cannabis, so take what I said with like half a grain of salt.

If its bottom larf just chop it off. Your exactly right. It will allow the plant to focus on the tops.