Hi Kenneth
I recommend taking a Sony A7r II Will give you the best quality and it is small.
Regarding lenses is all up to what kind of images you shoot. I tend to go for fixed focal length for minimum size but the system has great zooms. btw if you worry about quality, both Fabs and I, sold all our Leica equipment (M240s & Monochroms) when the A7 II came out. We didn't think the A7r was any better but the ... II all of them, better all around.
Regarding lenses, we did use the Leica lenses for a while but started seeing the Sony/Zeiss bing as good. I can recommend all the Sony Zeiss with the exception of the 24-70 f/ 4.0 .. it is not a sharp lens, we had one and went back right away. Since, a new 24-70 f 2.8 has come out and it is superb, have one and like it. btw this is not a Sony/Zeiss but a Sony G.
The other lenses we use, believe all are Zeiss except the 28mm being a Sony which not exceptional but can't complain with the price. 55 1.8, 35 2.8, 16-35 4.0 and will be getting the new Batis 18 2.8 They also have some Zeiss manual focus lenses which we don't have any.
Regarding the bodies, will be either the A7 II or A7r II The A7s II or even the plain s (identical except does not record internal 4k and a few other features) has the same quality. The one we gave up the Leicas for was the A7 II, also have the A7 r II which is better, 42MP vs 24MP and better performing in low light.
For the price difference, it is a tough decision, almost twice the price but slightly better. You best bet before spending a penny is to rent one. Keep it for a week and then decide what you want to do. Seeing is believing. Can't imagine towing around a Dslr. Oh, almost forgot, with the Metabones adapter Mk IV you can use your Canon Lenses with full exif data recording, functions etc. The lenses are just bigger/bulkier for the most part. Only have one Canon lens 24 tilt/shit. For renting can use Lens Rentals.
If you were wondering about negative points for the Sony, there is one and a big one. Repair !!! We had one of the A7 II go down in Iceland, Fabs fell in the water at the beach, got caught with a fave ! Huge one came in and soaked her, she was fine but not the camera (nothing unusual) weather sealing would not have help. Went to Sony and it has been a few months.
Apparently (close to 100% certain) Sony does no do the repairs, is sent to a center to do for them. My answer to this problem .... with the A7 II you can afford to have a spare and even replace if needed. He have thousands of images without a problem other than the dunking in freezing salt water.
Anything else will be glad to answer ... btw regarding ISO, we don't even clean until after 3200 and will not hesitate to go as high as 64,000 for keepers if there is no choice, will need noise reduction and the image can't be overall very dark, mainly shadows !
al
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