Pets really make the difference. Dont go wasting everything you have on pets you won't be using. Choose a pet and make it as powerful as you can. Humanoid is usually the easiest to get because the primary skill is always heal and the secondary skill can be mp heal. Once you have those two skills on a pet, level him and make sure you cap the skills before fusing them. Or else you'll end up with a low capped pet.
The best class to farm is still wiz. Farm pots like crazy and make yourself a doom bow archer/huntress, then you will soulbound on everything instantly. if you don't want to use a bow class use rogue, knight, warrior. They really benefit from mpheal pets. With my level 65 heal and mpheal pet I can run around invisible with my rogue all the time without interruption....and my knight can stun bosses time and time again until I need to take a potion.
It's my opinion that bow classes have the most versatility. Very high dps and medium armor makes it suitable for all situations. Arrows have range and pierce, not to mention ctrap and some quivers paralyse mobs.
People seem to lie archer a little more. I like huntress over archer because it's easier to use and uses more of an AOE skill.