Arcane wheelchair says “the arcane-frame model doesn’t specify a trait to use when making an attack
with it. Instead, you use the Spellcast trait indicated by your subclass.” I am playing a druid whose spellcast trait is instinct, which I have set at +2. It shows only a +1 on my to hit with my wheelchair. My Agility is set to +1 which is what the other 2 wheelchairs use, so I’m assuming that is what it is using.
Thanks for the report, we’ll take a look at this and see about getting it fixed!