This combination has a huge amount of natural synergy and brings to mind one primary thing: stealth. Rangers and rogues are both masters of sneaking around and ambush tactics. Combining the two makes a shadow in the night that can strike with devastating force and fade away. Maxing Dexterity out as fast as possible is definitely the way to go here; it helps with everything the build wants to do. This is also another one of those combinations that will probably play about the same regardless of the ratio; you are likely going to be very sneaky and be able to operate in both urban and wilderness environments with equal facility. More ranger levels give you an extra attack and more hit points, more rogue ones give you more sneak attack damage. The rest basically comes down to archetype and class features and personal taste. [[Synergy Feats for Multiclassers#Ranger w/ Rogue|Ranger - Rogue chains and ideas]]