The graph below shows the daily APY vs the daily APR for staking LUNA in the past 6 months. The APY shown here is compounded daily instead of per block, so, the calculation for APY is (1.xxx ^ 365) - 1, where xxx is the APR for that day and -1 to deduct the original modal used. From the graph below, we can see that the APY and APR don't differ much from each other, where they are only about 0.09% apart from each other at the most. This means that daily compounding will not affect the returns much and that the stakers can claim whenever they feel like it without needing to optimize the returns.

Based on the graph below, it can be said that the staking APY is inversely proportional to the total voting power. This is expected as the rewards are distributed equally among all the stakers. With less voting power, which means that less LUNA are staked, the rewards are split among less staked LUNA thus increasing the APY and vice versa.