Here is my logo for your consideration. I created a customized wordmark/font, where the "t" has an arrow stemming off to imply travel. The arrow also points to "ad", which is set off in a separate color. The blue/green scheme was used to visually connect the logo to the earth (blue water, green land).
Thanks for looking. Comments/Critique are welcome.
#12, this is really cool and unique and exactly the type of logo we are looking for. Not necessary to be a "cityscape" but some design elements which are related to travel
Keep in mind what all you hope to use your final logo on. Some logos have a lot going on in them, and would not reproduce very well at a smaller size. You seem to be quite organize and know what you want, so I am sure you are taking this into consideration... but just a heads up.