Here are analysis graphs of coin supply and inflation over a one year period for the options in the poll. The important thing to ask is what will the "thing" of the coin be. If it is quick profits, high inflation and short lifespan then the POS staking % must be high. If it is retail adoption, longer term profits, longevity and low inflation then the coin must have lower POS staking %. The answer lies somewhere in the middle of these 2 extremes.
The POS staking % must be just enough to incentivise the miners to stake so that the blockchain remains secure and widely distributed. There must also be a match between adoption and total coin supply - it would be difficult for millions of people to use 100,000 coins for example, but it would take some time to get that sort of distribution. There must be just enough coins released into the market to match demand for use. I would recommend a 6 monthly monetary policy review of inflation, adoption rates and mining stats and do a fork with adapted specs accordingly to align to the market conditions. Coin halving in POW is a rudimentary automated attempt at this. With successful implementation, after 6-12 months there will be enough funds to hire the best devs to design spectacular wallets and implement whatever features and specs are required at the time to meet market conditions.
I think it is best to leave the high POS staking % to Spots and Co who are geared to R&D those types of chains and high coin supply. Too low and no-one will stake. Based on the graphs below I see the sweet spot and safest initial % being at 10% per month which is somewhere between 100-125% per annum. Both of these answers will therefore be ok whichever is the higher of the two in the vote.
The other important specs to decide on are the min and max coin age. Max coin age is easy and can be 30 days. Min is more difficult. Too low and it would be too easy to move coins around between wallets and exchanges with no incentive to keep it on any side, but it would help a lot to have lots of small stakes to keep the chain rolling smoothly. Too long and liquidity might be impacted as people will keep coins in their wallets but if lots of movement occur, there could be less distributed staking and fewer coins qualifying for staking to keep the chain rolling. I would recommend a lower min coin age of 3 hours to keep liquidity higher and to keep the options open. It might have a slight negative impact on inflation than the graphs below due to more smaller stakes happening and real compounding being stakely compounded.
All graphs assume starting coin supply of 141,195 and work on daily compounding. The more accurate method is stakely compounding but daily is ok for illustration purposes.
5% per annum / 0.41% per month. Total coin supply after 1 year 148,413. Total coin supply after 2 years 156,022
10% per annum / 0.83% per month. Total coin supply after 1 year 165,000. Total coin supply after 2 years 172,404
25% per annum / 2.08% per month. Total coin supply after 1 year 181,158. Total coin supply after 2 years 232,592
50% per annum / 4.19% per month. Total coin supply after 1 year 232,393. Total coin supply after 2 years 383,021
100% per annum / 8.55% per month. Total coin supply after 1 year 382,236. Total coin supply after 2 years 1,037,606
125% per annum / 10.80% per month. Total coin supply after 1 year 490,089. Total coin supply after 2 years 1,706,931
250% per annum / 22.73% per month. Total coin supply after 1 year 1,693,907. Total coin supply after 2 years 20,460,888
480% per annum / 47.99% per month. Total coin supply after 1 year 16,412,349. Total coin supply after 2 years 1,932,841,328
500% per annum / 50.41% per month. Total coin supply after 1 year 19,982,242. Total coin supply after 2 years 2,866,671,797
1000% per annum / 124.98% per month. Total coin supply after 1 year 2,646,050,378. Total coin supply after 2 years 50,946,611,318,415
Potential implementation method of a POS % halving after an annual monetary policy review, assuming that was the decision taken for 4 years in a row. POS % starts at 125% per annum and is halved annually. It does not have to be halved but can just be reduced according to market conditions. Total coin supply after 1 year 490,089, after 2 years 915,902, after 3 years 1,250,651 and after 4 years 1,462,110.