Honestly, +100% lifestyle costs seems easier then.
Besides, we don't give dwarves and pixies a discount
Well, for one, Dwarfs are actually not that much different then humans.... Their proportions (for the most part) are within human ranges, that modifying clothing is not as big a deal.... (shirts are not an issue as the base trunk size of a dwarf is similar to a human. Waist size is within human range, leg length is way off... which would require a removal of material... and skill to do so... But enough to off increase costs as a game mechanic?
Equipment for a dwarf, wouldn't need much change as well, since they are again, close to human proportions... yes they need a booster seat to see over a window and petal extensions to drive.... (or just a Rigger module).
AS to Pixies.... well these little abominations just need to be thrown into the fires of "NPC ONLY".... These little bastards cause so many problems simply because there is such a disconnect between their size and the real world that they AUTOMATICALLY create headaches for people with even a sliver of common sense.... (I refer you to EVERY. SINGLE. PIXIE. WITH. GUN. POST.)
These little fuckers create such issue I did a post with a Pixie sized cut out, and REAL guns to show just absurd thinking a pixie could use a gun really is..... and people STILL tried to argue that they could.
They are not human, and since they vanish after death, the argument can be made that there is NO cyberware developed that would work on them (neurological interfaces for a metahuman brain may not work with a Pixie's neurological make-up... they ARE innate magical beings with extra natural appendages, that alone means their brain functions are different from a metahuman.) but that doesn't stop people from trying to cyber out the little fuckers AGAIN!!
(not to mention explain how and why a Mega Corp would go through the trouble of capturing and vivisecting pixies for the end result of being able to sell them cyberware... to a species that technically can not pay for said cyberware... (Pixies are only recognized as Sapient by France Remember?)...