Eight Month Old Fraternal Twins: Pulling Up On Furniture As My Sanity Weakens

I have eight month old fraternal twin boys -- 36 weeks if we're getting technical. Baby A continues to Army crawl as a means of travel. Baby B ... well he's a different story because even though they are twins they are still different babies. Baby B is pulling himself up on furniture and wobbling his way through life.
Frightening.
Last week he woke us up around 5 a.m. and I went in his room to find him standing in his crib, holding on to the side. What the heck?!? He loves to practice his new trick until he's exhausted.
I finally understand mothers who told me they loved the newborn stage. I wanted to scream in their face as I functioned on a few hours of sleep and struggled to care for a colicky newborn and his loveable but stubborn brother. However, now I somewhat understand. There was a silver lining in the newborn stage: you put them down and they stay there. Yeah, you were exhausted, hormonal and delirious but at least they stayed put.
Now, I was OK with crawling but this new stage resembles death-defying stunts. His legs shake unsteadily yet he slowly continues upward, pulling himself up on the couch, pack n play, activity center ... whatever he can find. He attempts to move sideways like a trapeze artist, slowly grabbing the furniture next to him.
When I put him down for a nap he pulls himself up to a standing position at least five times. My new workout is going downstairs, waiting until he fusses because he knows how to pull himself up but not sit back down, then walking up the stairs, taking his hands and showing him how to bend his knees and sit. Then I go back downstairs and wait for him to fuss again. I can feel the baby weight shedding off my body like a dog shedding hair in the summer! Or not.
Anyway, my husband purchased a play yard off Amazon that's 26 inches high and 34 square feet -- I wish my high school math teacher listened as we attempted to measure their current play area and figure out its square feet. For shame! The play yard can be used indoors and out.
However, I still am confused about this stage. Should I follow him around like a helicopter parent, making sure he doesn't fall and hurt himself - I've saved him from bumps and bruises too many times to count already. Or should I let him figure it out on his own? The problem is I feel like I am neglecting his brother who quietly plays with toys and crawls around. I figure he's old enough to do something, hurt himself, and figure out he shouldn't do that again or is he not old enough yet?
Ah yes the saga continues. Just when I was feeling confident in my mothering abilities one of them has to go and learn a new and dangerous trick. Yikes.