The PS90 is a great suggestion! Good weight distribution, nice, compact rifle.
Fair warning, though: it’s expensive. The guns themselves are not cheap, and the ammo is relatively expensive and can be hard to source. OTOH, if OP goes down that road they can get a handgun that shoots the same ammo.
P90s are even harder to source; you need both SBR and full auto licenses, and they’re even more expensive.
If OP has time and money, absolutely. Otherwise, it’s more an enthusiast’s gun in the US.
I mean, a shotgun is going to be the best for home defense; even a double barrel carriage gun would be comfortably light.
But your point is on the nose: this isn’t for home defense, it’s for insurrection, and unless OP plans on training as a sniper, bolt action is a poor choice. Heck, a lever guide gun would be better.
But, as little as I like ARs, for the purpose they’re looking to fill, some AR 5.56 is probably best. ARs come in all flavors, but .223 is cheap and plentiful, and you look at Creedmore or Blackout, or other exotic calibers if you know what you’re looking for and you already know 5.56 isn’t it.