Unfortunately, the archer kit cannot dual or multiclass, unless you use ShadowKeeper to assist you. I believe there is a Mod that implements the Archer kit to the fighter class, which allows you to dualclass, but you'd still need ShadowKeeper to make I multiclass. I'm currently playing a Archer/Thief, and since they day I've discovered it, I've never started a game without it. It's too much fun: a lot of versatility, power, but also weaknesses. But I'll stop my advertisement for the Archer/Thief here.
You wanted to play a Fighter/Mage/Thief, but thought it was too powerful? Play the class and everything it has, but then as a Bard (Blade would be the best choice, probably). The Bard is the jack of all trades, master of none. He can do everything a F/M/T is capable of, just not as good. A fun class to use, truly, and one that requires quite a lot of work in order to turn him into a good character.
Ignoring that, a Ranger/Cleric is a fine choice too. Just do a search and you will find countless threads saluting the class’ power. Then again, I thought that was exactly what you didn't want: a very powerful character.
Choices.
