I completed my IFR rating earlier this year, the main take away for me was not learning area navigation or even how to fly approaches, but how to conduct a flight in an orderly and disciplined manner including routine "housekeeping" steps in the cockpit like paperwork management, task flows & timing, logical steps appropriate to the phase of flight,the mental discipline of instrument scan and interpretation, and flying to tighter tolerances.
Haven't done much real world IFR but the training makes VFR much more rewarding.
Commence slings and arrows,,, NOW