Clinton,  hello!   I think you will like the 3x4's once you get used to them.   The truckers prefer them also if you sell any hay...       We have done 4X4's for 20 years and really like them.   Tried many stacking methods and just depends on your labor situation.  Heck, even pickups and gooseneck trailers work and have a guy chase them around with the loader. 
         Those bales are light enough most loaders should be able to pack 2 if not 3 depends.   A company called Phiber http://www.phibercanada.com/grab1.htm  makes a bale grabber you might look at.   The neighbor used to have one and really liked it for stacking and loading bales.  But spears will work just fine too.
         As far as feeding I just put the pickup in low and get on the back and go to flaking it off...  We use tractors when its tough going but otherwise.
         How far south of Billings are you I farm and ranch near FortSmith, like to meet you someday...Goodluck!