Oh, but OP, yeah, you pretty much hit every nail on the head.

Dick meet stem. That's how you unweight the rear wheel. Get that technique down and then remove the stem banging process.
Yeah, it'd be easier to skid skinnier, higher pressure tires, but at 64" you should be able to skid just about anything.

Track stands, just practice honestly. Videos/tutorials won't help much after you have the basics in mind. Turn the wheel and balance. The rest is on you.

Clipping in, just more practice really. For me, It's easier to clip in fixed gear than freewheel. I just put a foot down and the pedal engages itself almost. Just practice.