With your short legs/ long torso dimensions you need to be careful. People with average proportions and position just need to get in the ballpark for frame size and adjust the stem and saddle for fit. But your short legs would tend to put you on a small frame, while your long torso would put you on a large. And the big unknown here is that you don't really know how much drop you want, and what you've been accustomed to is very little. So forcing yourself into a lot of drop seems unwise... plus it may be impossible for you to get adequate reach on a small frame anyway.
The 59 has a 180mm headtube, which is 10mm less than your current frame. Plus you can get rid of the 40mm of spacers... plus if you need to you can get a horizontal stem to give you another 20mm of drop. That's 70mm more drop than you have now. I'd guess that 70mm is plenty of room to experiment, and you shouldn't have any reach issues with the 59 and normal stems (up to 130mm). I'd go with that one. Or at least the 57.