Team Pitching Statistics in MLB

Why are pitching statistics so quirky?  For instance, why does a starter need to go 5 innings to earn a win?  And why should a starter get a loss if his team eventually scores more runs than he gave up?

 

There should be instituted a "Team" category of statistics for pitching.  These would be reserved for special situations, but they appear to be justified.  A "Team Loss" would be assigned when the starting pitcher gives up fewer runs than his team eventually scores.  For instance, say Gallardo gives up 2 runs over 6 innings, but leaves trailing 2-0.  Then, the opposition puts up a 4-spot against the relievers in the 7th, and the Brewers eventually lose 6-5.  Currently, Gallardo gets the loss, but this hardly seems to be an accurate description of what happened in the game.  This should be a "Team Loss."  Likewise, the "Team Win" could be instituted whenever the team wins but the starter doesn't qualify--let's get rid of wins for non-starters.

 

Additionally, the "save" statistic is currently very arbitrary.  Why a "3-run-or-fewer-in-the-9th" rule?  The alternate rule seems to be much more fitting: tying run at bat or in the on deck circle.  This should be instituted at any time, meaning that a pitcher could earn a save by coming in in relief during any inning whatsoever.  (Currently, the "hold" is the statistic for non-closers, but that rule follows the same parameters as the save except for the 9th inning requirement.)