Subfloor instead of breaking concrete?

I want to put a bathroom in my basement with minimal concrete breaking, has anyone tried putting in like a 6" subfloor to plumb through?

How high should the subfloor be?

Finding a way not to trip people is the problem.
Nobody expects a step up when they are there.
You are better off to hire a concrete saw cutting contractor.
They make nice clean cuts without dust.

If you do make a platform for people to step up onto, you will need at least 6".
the p-trap of the shower will still require that you dimple in the concrete.

I probably have to break up the concrete somewhat anyways because I have to move the location that the soil stack enters my basement floor, so you are probably right, best to avoid a sub floor.

But how do I know where to get the cuts made to tap into the existing plumbing? In the room right now there is the soil stack entering the floor, and there is a floor drain where my washer goes into, it is a p-trap.

There is also one capped 3-4" hole but I dont know what it is for, it is probably from the old drain system when they used to run outside sewer water through the house's drain system. (the house drain systems overflowed, so they are now all plugged off, brilliant planners in the 50's!)

How do I start planning where to cut the cement if I dont know what direction the drain lines run?