You do know that the guardian, is a slow, highdamage, class, that can kill alot, but not catch them....
With a sword you can teleport forward every 10 - 15 seconds and Judge's Intervention gives you another. There are a number of ways to gain Swiftness, and you can have a skill to bind an enemy to you. I'm sure other classes will be more mobile, but a Guardian should be able to get to a pretty high level of mobility.
Resurrected Holy Priest
A guardian can be equipped and traited to be very mobile. There is one trait that makes your standard sword attack give you swiftness on a crit, and another(stacking) trait which makes that same standard sword swing crit chance 50% higher. On the same weapon you have a teleport, and one of your last 5 universal abilities is a teleport all on it's own.
That's just off the top of my head, ontop of strategic barriers I'm sure there are other ways to close a gap(and I know of at least one way to make one, if need be).
Read the books imo. If you have an ipad or something you can download them from amazon for like...$4.99. I got em for 3.99 pounds each.
You get quite a good sense of the world and the profs if you pay attention to what your reading and what the chars are doing. Plus, everything will still be a surprise visually for you.
And yeah...sounds like you want a Norn Guardian if you want a magical sword-wielding juggernaut. Mesmers, although I love them, sound too crafty and posturing for you.
Toodles.