I don't know what your routine for cleaning up is but I don't find the big enclosure to be more difficult than the small one.
When he poops or urinates, I simply clean out all the substrate in that spot and clean the surrounding furniture (like caves, plants or so). Then I put some fresh substrate in there and it's done.
I only do a full cleanup every month or so and I change his water every 3 days.
And yes you're right. I don't know how much of a climber your BP is but if he is anything like mine, I promise you that this kind of enclosure is going to be great for him. If I'm awake late at night (like 1 or 2 am), I can often see him resting on the big branch on the right of enclosure. Recently I also found him sleeping on the ledge or just cruising around.