I didn't find postfix all that hard to set up. Courier, on the other hand, is a disaster area, which is why my mail server runs dovecot instead; the latter took little effort to configure, and works quite nicely across several devices. The really hard part was finding a halfway decent CalDAV/CardDAV server that didn't require undue suffering to configure; I settled on Baïkal, which works okay, but could be considerably improved upon.