I think route races are the easiest races to bet.  Pace is a bigger factor than in sprints.  I also thought more"shady" stuff went on in sprints.  I'm not saying fixes, but when you see horses win off layoffs, its usually in a sprint.  I also think you see more dramatic form turnarounds in sprints.  
With pace, a slow pace benefits the front runners, who haven't been used hard.  A fast pace benefits off the pace horses.  One of my favorite bets was any horse who finished fairly well after getting in a 3 horse duel, with the other 2 finishing well off the board.  Horses that close on slow paces should be upgraded.  Best advice?  Get the Racing Forms Simulcast Charts weekly and you can see what was a fast pace and what wasn't.  And only compare fractional times from similar distance races.  Don't compare fractions in a mile race to one in 1 1/16 mile race.