Why wold a Str 5 / Agi 5 arm cost different amounts for different people? It is the same equipment
Is it, though? In-setting, cyber limbs obviously differ between metatypes. If you doubt that, then I'd like to see your list of troll characters with dwarf cyberlimbs, or vice versa.
Sure, the outside could look different, but statistically they would be the same, wouldn't they? Unless you're trying to say that a Dwarf with 5 Strength and a Human with 5 Strength somehow function in some fundamentally different way... The whole point of the metatype adjustments being part of Lifestyles is so that it doesn't have to be factored into gear costs. I may not agree with it entirely, but that's the way they have it.
As for the cyberlimbs specifically, if we use my motors and gyros analogy from before: We'll say for each 1 pt of Str, that counts as being able to put out say 100 psi, and 1 pt of Agi is being able to move 100 cm/sec. (These are pretty much arbitrary numbers, so don't worry about it making sense the whole way through). So if we have 3/3, that's 300 psi and 300 cm/sec. And if we have 5/5 that's 500 each.
So the mechanisms of the cyberarm have to meet those "criteria" to qualify as that level of attribute, and getting a cyberarm to do that would cost a certain amount. Are we going to say that it costs less to make an Arm with 5 Strength for an Ork than it does to make a 5 Str arm for a Human? Remember that cybearms are completely robotic, they don't depend on the base structure.
Well part of what you are paying for is just the customization (or at least that should be part of the cost) so having more than one base limb to choose from that have different base attributes should be a standard thing. Otherwise they should be having just one base gun, one base deck, one base car, etc. and make the customer pay to customize it from there. Instead we get lots of base models and still get to customize all that stuff to a greater or lesser extent. That's my two cents.
Chrome Flesh added something sort of like that when they added Cyberlimb Optimization. Other than that, Cyberlimbs' only attributes are the Strength/Agility, and they are fundamentally supposed to be modified, so I don't think it is a good comparison to say that "having only one cyberlimb is like saying there is only 1 gun and everything is just customization"
But on that thought, I did think of a sort of compromise. Have a short listing of "customization bundles" for cyberlimbs, like:
Name | Avail | Cost |
+Slim (+2 Agi, -1 Str) | +1 | +5000 |
+Hefty (+2 Str, -1 Agi) | +1 | +5000 |
+Troll* (+2 Str) | +1 | +7500 |
*Only available to Trolls
Slim/Hefty isn't actually a discount, it's just balancing out +2 to one attribute with -1 to the other at the cost of one attribute increase. Slim could be "for elves" and Hefty could be "for Ork/Dwarf/Troll"
Troll gives them a slight discount, but I don't think a complete removal of the "cyberlimb attribute tax" is in order here.