Where could I store my assets in an emergency if there are no more bitcoins?
Before thinking about plan B, I think you should focus more on Plan A which is buying more bitcoins now while you can. Bitcoin will always be in circulation because in the future, more people will be using bitcoin as a payment option.
If you want a second best cryptocurrency for privacy, I recommend Monero. Transactions are private and it’s easy to maintain your privacy while making transactions. Monwro isn’t a pump and dump coin. It’s utility makes it a very valuable coin to buy.