Weakest class, What is the weakest character types in the game? Options

[Ryel ril Ers]

The topics a little bit strange, but i want to hear pros and contras of the "weak" classes.

One: The players see what are the worst choices, and which character better that position.
Two: There are nonliked classes and i want hear that they are really useless.

[trufa]

Holy Power: he get the base thaco of a level 10 fighter (always get better base thaco than a fighter/thief because the cleric level up faster) and 18/00 strength and +10 hp for 1 turn
Draw upon holy might +3 strength +3 dex +3 con you have 21 strength with it
Righteous magic: max damage and +10 more hp
Champion strength +3 more thaco optional because you lose your casting ability.
with staff of striking you can do 73 backstab damage in this low level (4x backstab only) but in the end you get staff of ram and you will be the third best backstabber after the kensai->thief and the assasin.
The one attack no problem if you want to backstab.
I not recommended the dual wield because you only put into one star to it. When they not backstab they can detect illusions, buff the party and heal, and there are some good offensive cleric spell too.

You are right, bur with 4 spell preparations to a backstab...
Those creatures, who really need these preparations, they are immune to backstab.
This can use maybe only against illithids