wood I-joists or floor trusses are engineered. You can cut the whole center out of a wood I-joist in most cases, but you can't cut the bottom of it out. If you cut a joist out and the kerf is in the clear span, it will crack or break. There are online span calculators available that you can figure your joist requirement with, but I can tell you that 2x6 is pretty much the smallest for floor joists over. That's 5 1/2" deep. Your basement is overall 22' with a beam over the center, so your span is only 11' on each side. It doesn't look like you can alter your joists, unless you want your family to collapse your floor during dinner one night.
I just paid a plumber to break my concrete floor and run drainage for a new full bath and laundry room and it was WAY too expensive. I think someone with lots of patience and some spare time could do the job in a couple weekends if they had some help. The difference between a macerator and all the gear vs. breaking concrete and doing it the regular way yourself, well the old fashioned way is cheaper. If you pay a plumber to do the drainage, like I did, you probably would come out cheaper with the pump. What about just breaking out enough concrete to get the trap down into the floor, might get you 4" extra?