Location of high terrain and airways on one side of the track as compared to the other should form part of the situational awareness as we go along the route. When rapid decompression happens at usual cruise altitudes of around 350, due to the time constraint we just do what is already considered. Presence of nearest suitable airport cannot be thought of at that moment nor there is any need for that ,because even if you land up some distance further up it is not going to make any difference. That will form part of the situational decision/Diversion once you have safely levelled out and taken care of other things. What is taught in the SIM is how to execute the manoeuvre swiftly. Commencing descent, initiating turn and freezing Mach in the first loop and refining those targets in the Second loop. However the very fact you commence descent without prior ATC clearance exposes you to some risk with other traffic but cannot be helped. Real life refreshers in TCAS for others.