Thanks for your suggestion.
We will see, if more people ask for this.

Though I do not think it's a good idea from a security point of view that WinSCP would cache credentials of all user's ad hoc connection attempts.

It would be great to add connection hostory cause some times you open one-time (as you think) connection and cloese it and lost creds. But with history you can reopen connection dialog save it or just reconnect. Thanks.

One more misconviently thing: you open scp connection and winscp says that only ftp connection available. Would be great if WinScp appear button "try with ftp"

At the end - WinScp very cool soft!