due to old age eyesight, I went with a 10" HD LCD-LED monitor and with the shoulder strap the extra weight is not bad. I wanted HD with a HDMI input for possible future Lightbridge setup, and I can playback from the gopro thru HDMI adapter in the field. But I had another major motivation in that I am a amateur astronomer and take astro photos thru my scope with a canon dlsr. I can connect the camera thru the HDMI to this monitor to better see if the often faint objects are in focus. The monitor is light but adding the Boscam 832 rec, and battery adds a little weight. I had preferred not to use a self contained monitor for the purpose of having multiple use options for the monitor and makes it easier to change to a different monitor down the road. I personally like the "bigger is better" when it comes to the monitor if you have eyes like mine, now I'm thinking like you, a 12"or 14" may be perfect. I can almost do without glasses with the 10". I wonder what is out there in those sizes in OLED.
PS My son bought me a 40" HD TV to use as my computer monitor, and watching my drone videos on it really is awesome, I think I could fly very well using it if I could get it around my neck (Maybe a golf cart custom setup???)