I'm a S5 Jungler Living in S4
I joined League during Season 3, and I've been jungling from the moment I hit level 20 and could purchase tier 3 runes. I played nothing but Nocturne until level 26, at which point I started playing Shyvana. Fast-forward to the present day, Vi and Skarner are my two go-to junglers.
But I'm living in the past.
Although I start either Krugs or Gromp depending on which side I'm on, I still always get both buffs on my first clear before ganking, mostly because I'm really paranoid about being counterjungled and losing one of my precious buffs. A Skarner without blue is a sad Skarner.

And these days I see a lot of people going camp > blue/red > camp > gank (i.e. leaving either blue or red behind).
I'm a creature of habit, and I'm able to go through my current route with enough health to perform a good gank and at least burn enemy flash, but is a route in which you leave either blue or red until after the first clear better? I mostly play teambuilder, and because of my MMR I'm constantly matched with and against people in plat or even diamond, even though my skill level is mid-high silver at the worst, mid-gold at the best.
Any advice on which jungle routes are best and why?