It's all about finding what works and refining, and ditching what doesn't in a Cali, isn't it?!
We've had ours 9 months now, and we're still finding ways of making life easier in the confined space together. We commenced van life in the winter, so we got used to doing everything downstairs as it was too cold to sleep upstairs for a lot of the winter months, but over the summer we've lapsed a bit and got lazy about putting things away at night etc. We'll have to retrain ourselves once the temperatures start to drop. I have, however, bought the most unattractive fleece ever made my human hands (leopard skin print - yuk! - hopefully no-one will ever see me in it!), which is good for sleeping up top in the cold - it's long enough to cover my bum and has a hood. I will try to stay upstairs for as long as I can. I really can't be bothered with a Cali topper.