I slept in my Black Diamond Megalight tarp in the BWCA. I had the windward 2 sides sealed up with a snow wall. I had the non-windward sides open about 1-2".

Observations: (1) I got lots of condensation on the tarp. (2) I got "snowed on" when the wind blew hard, with condensation coming off the tarp. I also got some moisture on my bag when the face opening in the mummy bag slid up during the night. (3) All the "snow" and moisture on my bag would evaporate/sublimate in 1-2 hrs. (4) it was pretty easy to shake out the tarp in the morning and get the condensation off - or mostly.

So my question is, is all condensation bad? Meaning, if the moisture is sublimating/evaporating off my wet boots and gloves under the tarp, and then freezing on the tarp, and I can just shake out the tarp in the morning, or dry it in the sun...

I had trouble setting up the pyramid tarp. The snow wasn't deep enough or dense enough for a snow anchor, and I couldn't find the right configuration of trees/rocks to get a tight tarp pitch - especially late at night when it was dark. I was thinking I might be better off next time using one of my summer tents with the "fast fly setup" (ground cloth, poles, and fly only. I am wondering what I can setup that is fast/light? I don't quite want to sleep out in the open because of the wind - but maybe that's the right answer.

What you are doing with the tarp is fine. Condensation is a fact of life when winter camping. Whenever I camp I always take my sleeping bag out to dry out by sublimation unless it's snowing.

You could look into some ice screws to anchor your tarp next time. That way you can anchor your tarp almost (think rocks) where you want.

Yes, your tent will certainly make things a little easier and also harder as you have to bend down to get in your tent but if your tarp system works then go with it.

As long as you are able to get rid of the moisture on your bag, the condensation isn't hurting anything. You might want to consider getting a bivy bag to protect your sleeping bag a little more.

Condensation is a fact of life. Sounds like you were successful in your management of it.

To not have the condensation on the tarp there needs to be more air circulation under the tarp so the moisture is not trapped inside an enclosure.

Typically a shovel can bring snow from where there is some and move it to where you need it. Scraping off a thin layer off the lake to pile it for snow anchors or using bags to hold a volume of snow.