I'm brand new to vMix and pretty impressed with it so far. One thing I'd like to be able to do with it and can't figure out how is be able to select the input to be previewed (and output if preview the preview is selected) from the MultiView Fullscreen. Is this possible and if so, how? I've looked and searched all over for a setting for this seemingly obvious feature.

Use Case:
Operator running multiple cameras from a joystick controller with a MultiView Fullscreen displayed on a touchscreen. Other more involved actions (such as overlays) would be conducted by another operator from the main vMix window (obviously on another monitor).

Thanks...

Maybe a bit challenging, but I would not use the word inefficient...I use shortcuts very often, just that I aquaint myself with how I set up my shortcuts, and never had any issues.....
There are also 2 software versions of control surfaces available....Thecloudmediagroup has one sold on itunes...think the last price was $4.99...works on ipads....used it, and it works great....
Here is the store link.. https://itunes.apple.com...surface/id978932322?mt=8

Here is the link for the other control surface.....$50.00
http://shop.njastad.com/...uct/category&path=60


so, do a search, and see which best serves you and the choice is yours to buy....There is also a hardware version that can be found on vMix product page.....

Then you should point out that shortcuts are good, but you will have to get aquainted with them, but if you use the standard layout, they all the same on any keyboard, but additional ones can be added.....and the whole thing can be customized.......I mostly use the default shortcuts, but I added for my personal use, a few more....e.g.: I use the left and right arrows to shuttle through my play list in the Preview window, and the up and down arrows for shuttling in the Program window....I would only use the Program shuttling for video clips, still images or slides that I know the order, or in some cases where it may be in use replacing powerpoint presentations....and I did a lot of that for a week where all I had was a flash drive with images that I arranged in the list to appear in a particular order, so when I was told by the presenter, "Next Slide", all I had to do is hit the UP arrow.....I can not do that with a Control Surface, and I had at one session, over 100 photos....and I had to display them live as the presenter was speaking, so Preview sometimes was ok, but when I did PnP display, a different story....but then again, I am always experimenting with vMix to see its full capabilities, so I have a lot of experience with short cuts......and yes, I have a control surface which I bought from 'Thecloudmediagroup'...but I use it in combination with shortcuts...