I've "consolidated" down to these calibers:

12 gauge
22 lr
9mm
223/5.56mm
308/7.62x51mm
5.45mm


My question is, do I just buy the caliber that's on sale at the moment (best bang for $$$) or do I "spread the wealth" and equal $$$ amounts of ammo for each caliber?  

If I go for the best bang for buck approach, I'll just be getting 5.45mm and 22lr for the next few years at least.  Spreading the wealth approach, I'll probably be pissed off at the small amount of ammo I'd be getting (but I'd be getting something for all calibers at once).

My current ammo count is:

12 gauge:  ~100 shells
22lr:  ~8000 rounds
9mm:  ~4000 rounds
223/5.56mm:  ~1000 rounds
308/7.62x51mm:  ~1300 rounds
5.45mm:  ~3500 rounds

As for reloading, tried it.  It's not for me.  Don't have the time, patience, or space for it.