Orderbooks being full, liquidity and volumes of different currency pairs that aren't USD, JPY, UKP, CNY or EUR growing year over year, and more mature futures and options markets would be healthy.

I don't have any evidence to support this claim but I believe having these would reduce Bitcoin's price volatility and make price discovery much better.

It's a big ask to want Bitcoin balances on exchanges continually going down while volumes increase. But that would be the most ideal outcome for the Bitcoin market rather than a sudden upward spike in price or the usual frenzied bull market.

The end goal of course should be to move from valuing Bitcoin based on orderbooks to valuing it based on prices of goods and services as expressed in it.