All locations other then Special Random locations are mission based but some you can put off till later.
Spoiler The Kansas City mission with the Nuke you can leave till the end.
When I do the St. Louis mission I normally load up with repair kits. Some hints you might not know
Spoiler Have your people in the APC or any vehicle, crouch or prone. It will improve their aim. You can repair vehicles while inside them. Also it might take some time but you can drive the APC up that ramp to the Super Mutant Base on the Hill. It's very hard because they are well armed as you know.
I usually have a 3 tier fire system, when the situation allows, a couple standing shooting over the crouchers heads and then finally lying down stance shooters, usually my snipers, so none are receiving friendly fire but against overwhelming firepower everyones usually on the ground or crouching at a distance to draw some fire (from another rocket launcher mutant) away from the squad members who have to kill that particular (other) Rocket launcher Mutant. But the crouchers are usually my SMG/Shotgun/Heavy Weapons squad members for when my snipers get rushed by enemy forces at close range, the other squad members who are standing usually have machine guns for close and mid range attacks. I mostly clear the area before I bring the APC in, clear mines etc and heavy weapons enemies out of the way first with snipers. That APC mission I found Sneak was of serious value to get my squad into position to deal with those mutants, it was like that bit in Saving Private Ryan when those guys are on the Tiger Tank and the Germans bring out the 20mil Cannon, it was an absolute slaughter fighting those Mtuants, my team were repeatedly and literally shot to pieces lol, loved it tho, good challenging mission
Nothing Medical is helping these guys, I've tried Doctor Skill, First Aid skill, doctors bag, first aid box and the camo first aid kit to try and heal these guys, it does nothing is all it keeps sayin, tried nuff times, they're screwed