An alternative to the smaller inventory size is to make any item Wheeler carries have a reduced maximum stack size. You would still have the ability to carry tools and equipment without issues but reducing stack sizes could make carrying large amounts of resources more difficult. It could also be a bit tedious when transferring items from chests to inventory, although hopefully not annoying.
Additionally, Wheeler is the first character to have a higher base speed. Which just feels weird, speed is the most overpowered stat in the game, every other character who has an improved running ability needs to do something in order to attain it.