WOW! I'm elated to see so many well thought out responses tossed my way on this topic. I should state that when I speak of "activity" levels I'm being very general. There is an understanding of snake to snake (individual) behavior and differences in activity based on species and their specific habits. I fully believe the carpet python group will be more active than royal pythons, blood pythons and other similar animals but will not hold a candle to some of the colubrids that are much more active in general. I don't have a large study group here and can only go off my experiences with other snakes that I've observed and my own collection. Most all of this is based on the captive environment which is obviously very different from the wild. I have also taken into account what I've read in books and other media plus I'm adding YOUR (the forum community) experiences in to get a wider range. I am a rather big believer that a "fat and happy" captive snake will be a boring snake. Boa constrictors are some of the most consistent eaters, rarely refusing a meal, yet they are one of the first types to become overfed, lazy and often they die an early death because of excess stores of fat. There is a bit of a learning curve to properly figuring them (boa constrictors) out, at least for a serious keeper that wants to see a snake live beyond 20 years. Being acutely aware of seasonal changes, hours of light, humidity and temperatures is important and will play a role in longevity and day to day behavior. I keep my guy lean and he is off feed in the winter. Because of this, he is probably more active than the average boa kept by an overzealous keeper that enjoys watching weekly feedings. I'm not a breeder nor do I plan to be so I won't even touch on the effect of reproductive pheromones and their related cues that alter activity and behavior. I'm WAY off track LOL! Anyhow, I think because I like semi arboreal VS completely arboreal or completely terrestrial I'm very inclined to look at bigger coastals (mine is a mutt) and possibly a dwarf or super dwarf reticulated python. I had considered a Timor python but I'm hearing a lot of poop and pee and musking reports. Even the retics generate a lot of waste fairly often. I think the carpet group or another locality boa constrictor would fit here best but that doesn't quash my interest in the right olive or possibly smaller reticulated python. Personally, and this is only my experience my carpet seems to be the most active and social of the 3 snakes. She would get the nod if the boa constrictor wasn't so fun and impressive to handle. She's actually all over the cage as I type this. She has been active all morning and it is splendid! I could probably send my wife into a frenzy if I just got another carpet and boa. Problem solved LOL!