Ethereum looks to be less volatile these days. It is not rising but at least it's not dumping as well. I think Bitcoin technology is more basic, while Ethereum's one is more complete and you may get more uses of it.
Depends on the type of stability we are taking about here. Stable price, yes. ETH experienced much less net volatility than bitcoin, at least it seemed to me. And as far as the network, I would actually say that the bitcoin network exhibits more stability. ETH is much faster and much cheaper. But the smart contracts, the crowning jewel of the ETH network, is pretty much as good as its lowest hanging fruit, which is some of these jankily programmed contracts.
More features? Yes. Price more stable? That to. Protocol stability? About the same.
Just a matter of perspective