Hi!
I'm not sure how experienced you are, but generally I find that tines are very seldom the problem. They last very,very long.
The sound is dependent on a whole bunch of parameters, that need to be optimized.
Bad sustain can be caused by rust or oxide, dry and squashed grommets, loose screws among other things.
Low output has to do with pickup position and differences in timbre depend on all of the above plus the tines position in relation to the pickup.
Dampers and escapement also have to be inspected.
Actually, the last thing I try, if I can't get a note right, is to replace the tine.
Good luck,
Freddan