Really just depends on how many transactions you are dealing with. I normally never import my statements since they are only 20 or so per month....I keep up with my Payments and Receipts weekly via manually entering by checking my online banking register. So its only like 3 or 4 manual entries per week.....point is by time bank statement arrives I usually just need to check what was final bank balance matches state balance.

If you use Bank Recon module I think it makes all this easier since you will now get a "Cleared" field in Payments and Receipts (one thing Manager does it hide or show fields depending on what modules are activated, so if you activate Bank Recon you now get a "Cleared" field in Payments and Receipts)

Control Accounts are very cool....I've never used them but was good to see a video on them. So yeah, you can setup your CC via a control account and then use Inter-Account transfer to "pay off the CC" from bank account.

As to import CC statements, if its lots of transactions then yes would make sense.