um... why do you not want a secondary class? they add stats and skills to make your night better and to be able to get into the end game instances as a tank you will need to be gimped with good equipment and you should start doing that as soon as you start running DoD. you will have to get better stats when you get to like 60-65+ but you will use them for awhile so they are useful... and if you want to be really good at siege then you will want that secondary class and gimped equipment which again is not hard it just takes awhile or you could always go Priest/Warrior and be a healer that does bad ass physical attacks and is meant for soloing things if you want to see the power of one go to youtube.com and type in runes of magic battle monk
Reni:
Kallic Mage/Druid/Rogue 57/38/27 Phoenix (RETIRED)
Artemis:
Genicarus Priest/Warrior 15/15 Orion
Me when I wonder why the hell I decided to play a BattleMonk
~Just returning after a long time away~