You *can* recharge a Suica with a credit card but not as a visitor -- you would have to have either a special Suica-linked credit card issued by a JR affiliate, or a Japanese mobile phone that has a Suica chip inside. Same general rules apply to PASMO and the analogous products in other regions of Japan.

AFAIK the NEX+Suica combo is the only way to buy a Suica with a foreign or otherwise non-affiliated credit card. You would still need cash to recharge the Suica once you have used up the credit.