Monks aren't quite as scary as they look, because they have a harder time with magic items than most other combat classes and they rely heavily on having many good base stats, but it's sometimes a boon to not be so dependent on magic swords and armor. They're great if you enjoy being a decent front-liner and you want decent skills, great mobility, and having stronger defenses against magic attacks than melee attacks. They make great mage-killers. I suggest taking a couple of grapple feats and crushing the life out of any spellcasters you encounter.
As for clerics, they're one of the most powerful base classes in the game, in exchange for the not-so-fun role of spending a lot of spell slots keeping their comrades in the action. Their skill selection kinda stinks, though. If you don't mind being support and being accountable to a church/god, I say more power to you. There are some good prestige classes out there for them, but they tend to be limited depending on what god you worship. If you're starting at low level, I suggest you persuade the party to get you a wand of Cure Light Wounds ASAP, it's the most economical way to heal once your spells have run dry, and there are going to be situations that you just have to heal through.

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