I feel like a bull in a China shop at the moment. My goal is to buy Altcoins using fiat money at first as long term investments. So would like to use Credit card/bank transfer and use an exchange with the biggest variety of coins. I have tried to read some reviews on some of the exchanges and it all seems a bit frightening with lost money, no response to queries, downtime in websites. It seems like the Wild West out there.
I have tried just opening an account with Bitfinex and not able as no new accounts are accepted due to some problem.

Which exchange would you suggest to buy altcoins?