Hides are wonderful. I also like perches. Boas are rather active snakes if fed properly. What I mean by that is if you don't over-feed your boa, it will have reason to hunt and explore. There is more to it than that, but proper feeding goes goes a long way.
I'm not sure about browning out. I'm not a morph enthusiast, but I will say often, with age snakes will darken.
I have not experienced that with my locality snake just yet. It is a 4 year old and his colors are stunning to this day.
The boa's cage. Two big tortoise shell hides and 4 different styles of perches.
I can't recommend boa constrictors enough!
We have a royal python here, and no offense but she's about as interesting as the hide she stays in.