If you are talking about expertise (lv2 rogue - bonus action to use hide/dash/disengage), it's currently not really well implemented ; all characters have already those action as bonus ones (saving dash wich is only available to rogue).
Currently expertise is a bit meh and need slight balancing IMO.
As for you multiclassing, Starting rogue may be more beneficial since you got 4 proficiencies + 2 of them doubled (not implemented currently), and most of weapons peoficiencies available.
Going ranger afterwhile with multiclassing (starting after rogue lv 1 or 2 for example) should gives you most of weapons proficiencies + medium armor + one more skill, while still benefit from sneak attack, wich is not bad at all.
Better ask this after multiclassing completed (probably with final release, unless they introduce it for testing purposes on existing classes wich could be great :p).