...proof of steak...
Nice one

it could make a career like hodl

But back to your question: Each proposed proof-of concept has its advantages and drawbacks. My personal opinion is that the futures lies in a combination of different concepts. There are already coins which uses POW and POS or POS and POB* or even maybe POW, POS and POI**.
* Proof-of-Burn
** Proof-of-Importance