Windows point-and-click logging software for putting paper logs into electronic form, is exquisitely painful. So many points and clicks and types and point and clicks and type to fill out the form for each QSO.
What you want is a way to type in text (one line per QSO) and use a "Cabrillo web form" to get the formatting done. So much easier. Like these: http://www.b4h.net/cabforms/
Sure is is true that electronic logging programs are not very efficient for post operating log entry but it can be done. My main concern would be does an online format (like you have recommended) have the capability to download the entered data back to the ops computer in a recognized format (like ADIF) so it can be imported into an electronic logging program for later use if desired. If not, then for any use other than submitting a contest log in Cabrillo format, it is useless and a waste of time and energy. I, for one, would hate to enter all that information into a system where I could not retrieve the fruits of my labor for use past the one-off log entry to a contest group.
To the OP, I still would suggest that if you are looking to start using an electronic logging program, bite the bullet and decide which one you want to use. Set it up and start entering data. It isn't going to get any easier as time marches on. Logging mobile operations in general and especially time critical log entries like the CQWW 5 day deadline make the task more daunting than most. When I ran a lot of mobile HF operating, I never found a easy simple way to log mobile ops. The best way I did find was to record the QSO info on a handheld voice recorder and then transcribe it as soon as possible thereafter to avoid having a large backlog of entries to process. It always seemed to be time consuming for me regardless of the different approaches I did try.