Red Zone is crowded on the rail, empty at the back. But a rail spot in RZ is great, particularly for the kids. Unimpeded views, very close to the band at times. How badly does friend's hubby hate crowds? A rail spot makes crowds much more bearable. Being stuck in the middle of a heaving GA crowd sucks, but being on the RZ rail you have nobody in front of you, friends beside you, & don't really notice the crowd behind you. Plus the rail offers something to hold on to (& even sit down against pre-show), making the standing experience not quite so energy sapping. If there's issues, getting off the rail & to the back of RZ won't be too hard, as you don't have that far to travel, unlike the front of GA, which would be a nightmare. Just note, that for 360, you could get a rail spot arriving not long before gates opened. For this tour people have worked it out, & you seem to have to arrive a bit earlier to guarantee a RZ rail.
If you don't want to fork out a load of cash there's one place in GA I've been recommending for shorter people & those with kids. You'll get good sightlines & it won't be as pushy as the front of GA. It's the RAIL BEHIND THE RED ZONE. It's up the sideline, sandwiched between the expensive seats & expensive RZ. So you get some of the advantages of a RZ rail, with good sightlines & something to hold on to. You're just not so close as RZ, but you only have to pay a quarter of the RZ price. Here's a pic of the spot.
I'd recommended this spot to someone with kids over on @u2 forums. It worked out perfectly for him.
https://forum.atu2.com/index.php/topic,31277.0.html
To get a rail here I think you'd have to arrive just before gates opened. So probably later than what you'd need to be to get a rail spot in the RZ.