Running a small little research around here. For example, Bitcoin has (or will have) a total of 21 million coins, tops. Litecoin seems it will have up to 84 million coins, total.
In your opinion, when a new altcoin is created, how many coins is just too much? I have seen projects with like 10,000,000,000,000 coins. That looks almost like... a spam coin :/
Depends on the valuation. An ideal coin must be priced somewhere between $0.1 and $1.00. In case of Bitcoin, it is 4,000 times higher than the upper limit. This causes a reduction in the acceptability, since many newcomers may think that BTC is too expensive.