Pausing a print

I've had the same 'stuck-forever' experience before - although I think it depends on many factors, not just the cooling cycle.
Your idea to harness this power for evil is sound, however you may find that letting the first layer cool completely will mean when you restart the 2nd layer will not bond very well to the first, and may even split here if there's a lot of thermal stress in the print. That said, the experiment couldn't hurt, let us know how it goes...

To return from where you left off, just heat everything back up, and reverse whatever manual movements you did - you need to put the nozzle back where it stopped yourself before resuming!

If you wanted to automate this, in RH, slipping:

@PAUSE

into the GCODE will do exactly what the pause button in RH does. This is interpreted by RH, not by the board, so won't work if you use a different host. You can also add the lift up and bed temp stuff with G codes in the same place. Stick something like the following in between layers 1 and 2 in the gcode (if you're having trouble finding them, add a comment e.g. "; layer change" into the layer change g-code option in slic3r, and it should put that between all of them).

G91 ; set to relative positioning
G1 Z10 F1000 ; drop bed 10mm
M104 S0 ; turn off extruder heater (avoid clog)
M140 S0; turn off bed
@PAUSE
M140 S110 ; set bed back to 110C (change 110 to your normal bed temp)
M190 S110 ; wait for bed to reach 110C (")
M109 S210 ; turn on h-e + wait until it reaches 210 deg C (replace 210 with your normal temp)
G1 Z-10 F1000 ; return bed to previous position
G90 ; return to absolute positioning

Note that's all untested, keep an eye on it the first time... and good luck.