What does slow-motion have to do with casuals and soloers? Well, many casual are older customers that - you know - have lives they aren't willing to sacrifice for game time. This is generally accompanied by aged-neuron twitch and reaction skills and a rather fumbling keystroke method. While I came up with this idea for the benefit of reaction-challenged players, I realized that including John Woo directorial capabilities in an MMO would be a million dollar idea for any MMOG.
The simple way to install it is to just provide the player (or group) with the ability to "lock" an encounter, which removes the capacity for others to interact with their fight unless accepted into the group (which would immediately change the new member's video speed setting to whatever the leader has it set at). The player/leader has the option of setting the fight at one-quarter, half, three quarter or full speed. Any players outside of the fight would observe a slow-motion battle from the outside.
One of the things that I always disliked about any game was that I would be forced to put my attention on either watching the graphics on display and enjoying the cinematics, or I could concentrate on fumbling around on the keyboard and figuring out what to do before I got killed. I'm an old man; it's one or the other for me. Sadly, I can't really enjoy most of the cool battle graphics or mechanisms because I'm always too busy trying to figure out my next move or find it on the interface.
Now, if I could slow the battle down to quarter speed, then I have the ability to not only queue up my input (and change it if necessary), but I can also take the time to luxuriously operate my camera and swivel it around, zoom in and out, take screen shots, etc. I would have John Woo - like directorial control over my in-game experience. I can even zoom in on my character's expressions, for crying out loud. Also, any other players who were interested in hanging around and watching the battle would be treated to slow-motion visuals, allowing a much more theatrical experience.
The slow-motion option also fits in with the overall framework of the sandbox-style offline advancement character development game; combat becomes more about strategy than it is about twitch and reaction skills and how much you've memorized about what to do and when. Even if you're grouped up with others, you have the time to ask questions and the leader has the time to instruct others or command them. Talk about casual-friendly; I don't mind if someone knows more about a fight than me, but I'd appreciate having the time for them to tell me what the strategy is, and then being able to respond, with more than 1 second to accomplish it.