I went through a thorough process in deciding which camera platform to purchase about 5 years ago and I settled on the Arca Swiss.
The reasons for this were as follows:
-I found it to be the most compact of the options while still allowing for a limited amount of tilt or swing.
-The focusing helicoid and tilt/swing functions are built into the body which means you do not need to purchase those every time you have a lens mounted. This lowered the price of purchasing a new lens by about $1000-$1900 depending on the corresponding body and whether or not you wanted tilt/swing.
-The helicoid is larger and more precise, which is a plus when dealing with wide angle lenses that have much lower tolerances in regards to obtaining critical focus.
-The lens mount was designed to work with or without a sliding back without requiring the need to send the lens back to get remounted.
-The additional spacers supplied with the lenses to compensate when not using a sliding back could be stacked on top of each other allowing for table top and macro photography, so long as you had at least two lenses. (Not nearly as good as using a bellows camera, but better then the other systems.)
-The less complicated lens mount design allowed for you to easily swap out a shutter on location if the one on the lens went down. (I have needed to do this once so far; takes about 5 minutes if you carry a spanner wrench with you.)
-Only the back of the camera shifted. For the Alpa, you need to buy an extremely over priced adapter for this.
-Any Acra Swiss body will mount onto any Arca Swiss tripod head without the need for a plate, so you don't need to worry about always having one.
-Arca Swiss makes a bellows camera, their M Line; Apla and Cambo do not.
-The RM3Di's back mount is the same as the bellows mount on the M Line, which means you could use the RM3Di as the front standard on their M Line cameras.
-Any lens mounted for the R line can be used on the M line with a simple bayonet adapter plate.
Insofar as lenses, I use the SK 35mm, Rodie 55mm, and the Rodie 90mm (previous version that does not require the extra box, still super sharp by today's standards).
The SK 35mm does suffer from lens cast on the 60mm backs, but with the current version of C1, you can get 14mm of shift. With additional work, you can get up to 18/20mm of shift, but this will require additional layers in post to bring back loss of color saturation and correct magenta hues that the LCC did not fully remove.
The Rodie 32mm is your best bet for future proofing the system, however it is a $10K lens. It also has an unique distortion that can be removed in C1, however you need to keep track of the shift for each image. Not a big deal when you are shooting tethered, but a pain when you are not, like with exteriors. Also, the front half of the lens is so heavy, it is adviced not to walk around or swing the camera with the lens mounted because this could torque the shutter.
I do use a sliding back and prefer this over live view or the view finder. Live view sucks and eats up batter life; the varo-finder is well thought but you are not actually seeing your true frame. I use a Kapture Group sliding back, which is smaller and lighter than the Arca Rota-Slide, however KG is no longer in business. The Rota-Slide would be great for studio use, and it is better made.