If the water sitting in the plumbing from when you shut off the water in the morning turns rusty, that says your filter and softener are not removing all the ferrous iron in the water and it is converting to ferric iron (rust) in the water during the day causing orange/brownish water by the time you get home.
Two ppm of iron is very difficult to live with. And IMO your filter and softener look small and will be too small for say more than 2 people in the house. And that assumes no more flow than 9 gpm. And that may be too high for the softener.
A check valve is not to protect your house, it is used to protect the city water system from water from your house, an outside faucet etc. backflowing into the city water to contaminate it as it goes past your house on to other customers. Same for the vacuum breaker on outside faucets, while that 'protects' you too. How the hell we survived with indoor plumbing for a 100 years without those things is beyond me. A pressure regulator valve protects you from excessive pressure in the city system until they break.
You should test for iron and maybe tannin in the raw water and in a sample after the iron filter and then the softener. That will tell you what the equipment is doing and how good or not.