How short is too short when it comes to stem length? I ordered a 70mm stem to replace my 80mm. I would get a smaller frame, but I absolutely cannot find anything under 48cm for a decent price, and it doesn't help that my ape index is -2.5". This is on a road bike btw. I'm also not a fan of how the steering feels and I would hope that a shorter stem would mitigate that.

Also, does the reach of quill stems measure the same way with threadless?