I'll offer this in regards to R/O water... Look at R/O as starting with a blank slate. You don't have to worry about what's in it and what's not. You can tailor for a strain by adjusting things like more/less
cal-mag etc (not saying you can't with tap, I just find it easier). Pure water is one less variable you need to worry about should you have issues. R/O systems are extensible in that, if you need more flow, you can add on to or buy a larger capacity system. I swap filters every 9 months to a year with high tds inlet water and a hell of allot of flow. A simple pre-post tds meter will keep you on schedule for filter changes and a pre filter pump will boost pressure if you are not seeing enough flow.
If you do not go R/O, have a water quality test done to determine what is in your water and what is not. Find a good sediment filter or a series of filters and it may work perfectly for you. From years of experience I can tell you first hand though that a quality R/O system is more than worth it's weight regardless of waste (and a little creativity and you can put the waste water to work as well).