perks of MB in SL?

[MiRai]

I plan on boxing in retail for the first time for the upcoming SL. I was thinking of trying x5 druid and trading heroic gear to my rogue main. But that seems out of my skill level considering classic is mechanically easier than retail. And it will only be useful up until I get min ilvl for heroic que.

At first, I thought you meant trade heroic raid gear to your Rogue, but then you mentioned "que" [sic], which made me then assume you were referring to heroic dungeon gear. With that said, I will say the following...

Personally, I wouldn't think that jumping through the hoops of choosing a covenant and gearing a team just to do heroic dungeons and funnel that leather gear to your Rogue is going to be all that engaging, and by the time you reach the point where you're able to do that you could've just played the Rogue solo and been grinding heroic dungeons for the gear to begin with. As the expansion plays out, heroic dungeon gear will be pitifully easy to come by as the overall item level ceiling continues to increase with each patch, while heroic dungeon difficulty stays static and its rewards fall to the wayside, other than for maybe a freshly leveled character.

However, if heroic is the highest level of difficulty that you think you can handle, then no one can tell you what you're going to enjoy, but I have a feeling that you'll eventually find heroic dungeons to be quite a pushover, which may then push you into the territory of mythic. Ultimtely, that may also depend on how heroic vs mythic dungeon mechanics end up playing out, though.

Besides herb/mining and my "meh" idea, is there any benefit to MB?

Not to sound like I'm vilifying you, but not everything is about taking advantage of a system, and sometimes the "benefit" is just about having the opportunity to play the game differently, on your own schedule, with an added challenge.