It is possible that Freicoin runs into the same problem as bitcoin because the mining reward is not compounding.
To be clear, Moore's law is equal for all miners, honest and attackers, and by the way, it's not a law.
You don't need compounding reward.
Does it have to be compounding on nominal or real terms?
1) Since it is not compounding the 5% surcharge will always have the same mining profit unless the price of the coins increases. An inflationary crypto, mining profit increases if price remains static.
No, no. Mining profits don't necessarily increase if the price remains static. That depends on how many other miners are out there.
Ideally mining profit tend to zero in perfect competition in ALL CRYPTO-COINS. The only thing that would change (with ideal perfect competition) would be hashing power.
Profitability depends on competition, not on nominal reward. And the difficulty filter tends to adjust even if there's only two miners.
2) the 5% surcharge makes it easier for a miner to accumulate a share of all coins proportional to his share of mining hash in a period of ~30 years.
Sorry, I don't understand what are you talking about here.