Looks like this topic is a thing of the past now, but I still wanted to reply if it's just the same :P Anyhow, I love marleybone. I've always had a thing for England, and as this world is a play off that, it's right in my bag. I also love love love the Sherlock Holmes books, so I get super excited whenever I'm given a chance to talk to Sherlock Bones on the game, haha. I kinda wish he had a bigger part in the game, overall. Sense he IS a detective, it would have been cool if he popped in now and again to help us make sense of everything.
Marleybone is definitely my favorite world. Sidewalks were added in an update before I got there so avoiding them wasn't a problem. The scenery in Marleybone was gorgeous, and the music there is one of my favorites in the game, other than some Avalon themes. Lv.52
Overall, it's one of my favorites :D . Very challenging for that level and great music. On the downside, it's the hardest world (that I know of; I'm in Dragonspyre) to move around in without being pulled into a battle, as there are no sidewalks.
For me the battles are easy, (probably because I always tend to get the best gear for some reason). As for the sidewalk issue, just stay to the side, and on ramps ALWAYS walk on the outer wood. Do this and you will be able to pass through Marleybone unnoticed.