If the user attempts to spend more than they have, the wallet will prevent such a transaction from occurring..
All that is needed is just waiting. A user can write a transaction today, and it will be invalid. But if that user will wait a day, a month, or maybe even a year, then this transaction will finally be valid, because the amount will be increased over time.
If another user attempts to spend your funds, for example, a hacker, they must also know your pin.
If PIN will be the only protection, then what about bruteforcing it? In case of centralized systems, there is a limit of how many times you can try it. So, what does it mean in your system? Is it possible to attack random users, and block their accounts, just by endlessly trying invalid PINs on their accounts?
If a user attempts to do a double spend the validators will verify the first transaction but deny the second one.
How to prove to the new users, that the system is honest? New nodes don't know, what was "first" or "second", because they can only download the history. And validators can sign both versions to maximize their profits.
You receive rewards daily at midnight GMT.
Even in casinos, where you can earn 4% per year, just for holding funds, it is calculated at random time. Because in other case, it is possible to exploit the system, by depositing it "just before", and withdrawing "just after". Which means, that if your coin will be listed on any exchange, then users may just buy it "just before getting bonus coins", and then, use their bigger amounts, to withdraw them, and convert back into other coins, which are not printed out of thin air.
Also, the exact supply doesn't matter. But proportions do. Which means, if you for example double the amount of coins in circulation, then the exchange rate between your coin, and other altcoins, will just halve (or worse).
No coins are stored on the validator. Only wallets can contain coins.
In decentralized systems, it is not possible to separate roles. Which means, if you are a Bitcoin miner, then you can also be a Bitcoin user at the same time (or even Bitcoin developer). And here, it is the same situation: if you create for example two separate programs, one for the validator, and one for the wallet, then nothing stops the user from running both on the same machine.
30% annually compounded daily
Ouch. That will crash the exchange rate between this coin, and a lot of altcoins.