If you have Honda as second car, you definitely need to get used to catera's brakes lol. They are powerful enough but they never grab as newer cars. I even had GTo calipers, same thing, seems like pressure builds up within some time, not instantly, no matter how hard you press (speaking from autocross experience). My 14 ram 3500 diesel has similar brakes feel. Try to brake hard from 60 mph, when no one behind you, if it stops solid, nothing to do with it, if there is no power or feels not enough, or pulls to the sides, than you might have bad rotors, sometimes on the inner side, you can't see it until wheel removed or laying on the floor. I just replaced rear rotors on my wife's catera, had really bad ones from inside, and it did huge difference. I would check rotors if I was you. It's my 5th Catera, never replaced master cylinder in any of them, two current ones have over 200k now. Also brake fluid needs to be changed every 2 years, it's hydroscopic, means attracts water and becomes diluted over time, might boil or freeze and changes its working specs. Long travel might be because of air in the system. I think you better do overall check up and tune up such fluid change and bleeding first, before you start throwing parts at it.
PS. Try to press the brakes slightly let's say 2 inch, and wait if they start to grab or not with delay, mines would, right after brake light comes on, it's not crazy power, but it doesn't have 3 inch free play as in your case.
Good luck.
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