Quote from: Sixophrenia on January 21, 2019, 09:25:27 AM

Is there a list of PoS network approaches that I can look at?

Haven't seen a list though i just know of a few Randomised POS Network approaches.
Next block producers can be selected based;

- Coin age

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Peercoin's proof-of-stake system combines randomization with the concept of "coin age", a number derived from the product of the number of coins times the number of days the coins have been held.

Coins that have been unspent for at least 30 days begin competing for the next block. Older and larger sets of coins have a greater probability of signing the next block. However, once a stake of coins has been used to sign a block, they must start over with zero "coin age" and thus wait at least 30 more days before signing another block.

- Lowest Hash value and Size of stake

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Nxt and BlackCoin use randomization to predict the following generator, by using a formula that looks for the lowest hash value in combination with the size of the stake. Since the stakes are public, each node can predict - with reasonable accuracy - which account will next win the right to forge a block

More info here: Proof of stake

- Compliance level, Stake and Reputation
ORBS approach is through Reputation of a node's trustworthiness according to other nodes, minimum stake required for deposit and compliance which is the track record of a nodes behavior over time to ensure they are making required updates, maintaining fairness policies etc all combined together.

https://orbs.com/what-is-proof-of-stake-pos-vs-dpos-vs-rpos/