Greenmachine Loc: Chicago, IL

I'll jump in this discussion with my three cents! I have two Nikon cameras (D7200 and D750) both with 24 MPs and ISO is not one of my big concerns and I normally have them BOTH set at ISOs of 200.
Outdoors, ISO should never be an issue of you shoot shutter speed priority mode, determined by the focal length of your lens and bump it up another notch if you you're an old pro with shaky hands like me!
Indoors is slightly different: I shoot Manual or Aperture preferred and tinker with ISO until I have enough light (sometimes up to 640): USE YOUR EXPOSURE COMPENSATION if need be! :)

Don't let the ISO concerns keep you from having fun taking pix...shoot some black and whites when you feel frustrated and play with the contrast in monochrome mode...
---Greenmachine

dgolfnut Loc: Bear, DE

Thank you all so much. This is one active forum.

Distilling what I learned from the responses -
#1 - get the shot - I'll leave ISO in auto mode and maybe toy with limiting it's max value if I get unusable images due to noise when shooting low light subjects. When my skills and knowledge allow, I can modify my process and settings.

I'm just starting getting to know my new D750. This should be quite the adventure.