My Players Don't Like to Backstab

Maybe because I haven't been horrible enough with traps and that stuff, maybe because I haven't run enough hardcore oldschool, my players all hate thieves.
Not thieves that steal their stuff, but the thief/rogue/specialist/(also assassins) class. Most think it is stupid.
As a thief player myself this is slightly offensive, but nonetheless I have come up with a few ideas that may make them more appealing to some players who don't like the old-style sneaksters:

Special Backstabs
Many players don't like backstab because they feel that, at least at low levels, the risk is not worth the reward, the damage isn't high enough with small weapons and suddenly you're within range with few hit points. Here are some ideas for possible backstab alternatives:

Limb-targeting: Instead of stabbing the back, a thief in prime hidden-strike position can aim for the limbs of an opponent, opening up the opportunity for:

The Hamstring- in 5' scale, humans can move 6 spaces in a normal move. Roll 1d6 and you have damaged your target's leg enough to remove that many spaces from its move.

Alternately Aim for the Arm, mangle a hand or a shoulder on your opponent's sword arm to take your level off his to-hit roll. Possibly temporary, possibly permanent. Level could also be used for hamstringing, so that you have a semi-paralysing attack by level 6 or 8, depending on the monster.

The choke-hold might be included in these attacks. Try to silently choke out an enemy: add your level to checks (strength?) against the opponent's CON, which decreases by one point each round until he passes out at zero; use a garrotte for a bonus. It's more difficult, but with the potential to be extremely useful.

Chain Stealth: A skilled thief is a master of the shadows. On a critical backstab, might a thief be able to perform a silent kill and remain hidden without a check.
Depending on how much power you want to give, maybe the thief does this on any opponents lower than his level or than one-half his level. Maybe he can perform this power once per day, but that seems dangerously late-edition to me.


Special Trap-Working
See a trap, disarm, move on. Standard procedure. Alternatives?

Alter Trap: It might take some more planning on the DM's part, but it seems conceivable to me that one could keep a notebook page of common traps and what parts are in them. One need not even go this far to allow creative thieves some options in changing the traps they find.
For example, a pressure plate trigger might be tightened (something involving the spring?) so that it only operates under a greater pressure. If the heroes can lead the troll through that corridor... BAM. Advantage to the planners.
This leaves all sorts of possibilities for making dart traps launch other small traps, etc. A thief with a mind for tinkering might carry around small springs or wires to widen his options, so long as he can convince the DM that it seems plausible.


Locks
Replace a lock with a different one? Wire a trap to a lock? Put gunpowder in a lock and rig it with flint? There's something there.


That's all I've got for now. I may try the trapwork and backstab targeting. Please share any additional ideas.