CPU vs. memory-hard vs. Hashcash

[ArcCsch]

CPU coins (their proponents actually) claim greater decentralization and low barriers to entry.
I presume that disadvantages of CPU coins fall into two categories:
(1) Not a good idea in the first place.
(2) Someone can always make an ASIC.

Memory-hard proponents claim more difficulty in building an ASIC.
I presume that disadvantages of memory-hard coins fall into two categories:
(1) Hard to verify.
(2) Scrypt ASICs exist.

Some people claim that Hashcash is good enough, they claim that ASICs are reaching the limits of performance, and it would soon be practical for hobbyists and people in general to buy a relatively cheap USB and mine on a small scale, without it going obsolete in months. Others cite the growth of giant mining farms and are afraid of China dominating bitcoin.

What are the pros and cons of different mining schemes?
I am only comparing different types of PoW, not PoW vs. PoS vs. PoD vs. PoB vs etcetera...

[robelneo]

This is not in your list but I voted of for cpu ,proof of capacity is a good mining option it is asic free and any one can mine this coin,Burst is the only coin so far that is implementing this algorithm,they have a fast growing community and volume and price is spiking up,why not add this to one of your option.

[eckmar]

This is not in your list but I voted of for cpu ,proof of capacity is a good mining option it is asic free and any one can mine this coin,Burst is the only coin so far that is implementing this algorithm,they have a fast growing community and volume and price is spiking up,why not add this to one of your option.

I agree with you. Proof of capacity is great mining option. Look at the prices of storage in last few years. In next 5 years I expect that proof of capacity mining will be more popular due to storage price constantly decreasing