A long time ago there was a guy named Fer-Fal on several boards. He was from Argentina. The economy crashed so he was living through a SHTF and talking to us.
His comment on body armor/assault rifle was pretty good.
He thought good soft body armor was the first thing you get. You find something you can wear under other clothes. This will allow you to wear decent armor and be grey man. You could wear it around Chicago today. Maybe if things are active, you wear it while working in the garden.
Then you can think about the plate carriers.
In cold places, or really active places, maybe you do both.
As for what to get, I am not the man for this.
While Fer-Fal had very good input, it must also be taken in the context of the location and era it was given.
Some of it, is very useful, because people are people, and people act the same to similar situations in a lot of cases. But it pays to remember that Argentinians aren't American and vice versa.
Body armor has come a long way in relatively short order since he posted his information. To the point that full coverage soft, with plates thrown over top, is a combination rarely used outside of the police, or specific threat instances anymore. Today the most common body armor is a plate carrier with plates, and possibly a soft armor backer.
I have several sets of soft and hard armor I've acquired over the years, from full coverage soft armor designed to have a plate in a chest rig worn overtop, to minimalist plate carriers with stand alone plates, and two straps to hold the plates against your stomach. Unless there's a specific threat that mandates full soft armor coverage (like shrapnel/frag) or you're a police officer where you need full time soft (pistol) coverage, and have time to don your plates before a responding to a rifle threat there's very little call to wear a soft vest, and have plates to up armor over top. A modern PC is much more comfortable, ergonomic, and easy to use.