Utah's Neighborhood Elections force candidates to pay attention to rural areas 
of Utah. Direct primaries encourage candidates to ignore rural areas and
 communicate only by paid advertising. A direct primary would create 
fly-over areas of Utah that will rarely get to meet their candidates 
face to face.
Utah's Neighborhood Elections work to create a balance between population and Counties, similar to what the US Presidential 
Electoral System is designed to do. 
See also:
http://www.deseretnews.com/article/865588184/My-View-No-caucus-means-fly-over-counties.html
Why keep the US Presidential 
Electoral System:  
The US Constitution provided  for a
 balance between small population states and large ones. This is one of 
the  reasons for the Senate having 2 per state and the House being 
divided  based on population.
The current US Presidential 
Electoral System keeps part of that concept so that voters in 
California, New York, and a few others do not decide who is elected, 
ignoring the rest of the country.
The original system was 
designed so that the electors nominated two candidates, one not from 
their state, and unless there was a candidate nominated by the majority 
of electors, the voting for president out of the top 5 nominees was done
 by the US House of Representatives, one vote per state. If two 
candidates received a majority of electors, the House would decide 
between just the two. Basically, the loser of the top two became the 
Vice President, who would take over if something happened to the 
President. The elector college system protected every state from being 
ignored.
By 1796 and 1800, partly due to political party 
influence, and because the public didn't want the US House to decide the
 election a movement to change happened and under the 12th amendment 
this was changed. One reason was to make sure the President and the Vice
 President could run together. The change made it so the electors would 
almost always reach a majority and therefore cast the final vote, and 
because of that, most states have now required that the elector vote 
based on which party they represent. Utah requires that an elector be 
replaced if they do not vote per party.  See http://le.utah.gov/~code/TITLE20A/htm/20A13_030400.htm
Under
 the current system, Utah having 6 votes  instead of 4 gives us a slight
 edge over population. Utah has decided to have a winner take all 
system. If Utah were to  split our vote, it would carry less weight in 
the national election, but it would put Utah more in play. 
While
 the current system doesn't work as originally intended, there is still 
some balance favoring smaller states, just barely enough to encourage 
candidates to campaign throughout most of the country. Without the US Presidential 
Electoral System  , I believe that would be eliminated and I 
also believe the cities with the most population would be the locations 
where campaigning would occur, making the situation of ignoring parts of
 the country even worse.
Some information:
http://en.wikipedia.org/wiki/Twelfth_Amendment_to_the_United_States_Constitution