For ground work get a Speedbooster and use Canon EF mount lenses.
I LOVE the Rokinon14mm T3.1 Cine ED AS IF UMC Lens for Canon EF Mount on the GH4 on my Movi.
It's wide enough to capture awesome and yet doesn't distort.
Sample:
Cleveland is beautiful! Just a few seconds of our awesome community we captured today... #cle #cleveland #batterypark #edgewaterlive #movi #MōVImethod #airheadmedia
A video posted by AirheadMedia LLC (@SleepyC) on Aug 20, 2015 at 7:23pm PDT
I've been looking hard at all of those. I've noticed Rokinon makes a few MFT lenses as well. Is the main reason you are using the Metabones is that it opens up a larger variety of lenses for you?
Was that Slash at the beginning?
very worthy of your consideration and when you compare cost vs ef mount canon with speed booster you are way ahead of the game. much more compact and lighter too. http://www.veydra.com
Google around for sponsored and non sponsored reviews. They are all impressive. Cheers
Chris