His options are slim. Sha256 is a no go because miner support is low enough that they could be 51% attacked by basically anyone. Just Ocean aimed at Bitcoin is 3x the size of all of the hash pointed at bip110 right now. Another challenge is, finding miners. Switching away from sha256 means all the former bitcoiners now lukecoiners need new hardware in order to mine. Right after the switch there is likely to be a dominant player who single handedly controls the network while other supporters scramble to get hardware in place. That leaves the Monero algorithm. Intentionally designed to require general purpose CPUs. Then anyone can mine immediately on their existing PCs. The downside of this is that Monero requires regular PoW change hard forks as people figure out ways to cheat algorithms. This is all keeping in mind the cost of attacks. The cost of the hash pointed at the chain sets an upper boundary for the price. Too high price with not enough hash, you get 51% attacked. Monero already deals with issues with hackers attempting attacks using botnets. The $ value of their coin will not be even close to parity and people attempting to sell their shiny new doubled up coins only makes it worse.