1) Once all countries ban ICOs, the alt-coin space will be gone, including Ethereum.
Why would they ban ICOs, and why would that affect BTC?
2) Any bitcoin holdings might be considered illegal in a couple of years, due to money laundering and funding of criminal activities.
So cash was made illegal hundreds of years ago by that logic?
3) Too much regulation might be imposed that removes all anonymity and privacy making the coins unsuitable for any legal business transactions. All wallets and addresses might need to be registered with the authorities.
So it's both illegal and regulated? Also, how does privacy make it unsuitable for business transactions when bank transactions are completely transparent and used for most of them already?
4) Crypto coins will be pretty much limited to what they are meant for - just tokens to facilitate faster fiat transactions, but not to have any monetary value for tokens themselves. Ripple and some other coins are heading this way already.
Ripple is centralised and should not be regarded as a "crypto coin". You do not understand the purpose of cryptocurrencies.
If you're going to make negative statements about cryptocurrencies, please research them. So far it looks like you have no clue what you're talking about and you're even contradicting yourself.