If the system has worked well in the past and you've just recently developed a couple leaks, I wouldn't get too carried away changing component configurations around. Things may have deviated from mfg design criteria for a reason. If you know for sure that Harry Homeowner has made changes to the system, I'd be more worried.No way to know for sure but if it worked before there is no real reason to change it. Just fix the leaks, install new fittings and devices where the corrosion is and move on. And insulate the pipes. If the system has problems after, or there is more reason to change the piping configuration do it then.
Just to add a little more here, If you do have make up water continueing to fill the system after your at full pressure, You might want to make sure the pressure regulator on the fill line is closing fully. Could be some debris holding it open a bit
