Best to have a plumber inspect and advise you.
You could conceivably save $500 doing the concrete excavation yourself. Just remember you will have alot of rubble to deal with. Sometimes you can just pile it up in the crawl space if you have one. If you do concrete excavation, be careful not to hit the stack with the hammer.

: Breaking or cutting the concrete is the way to go assuming the main drain is below the floor level. Raising the floor is not a good option, it would always look like a jackknifed job. You can probably live with the 81" ceiling height in a basement bathroom unless you have a family of basketball player. Your best bet is to have a plumber inspect the site and give you his advise based on personal inspection. If you do proceed, you could save some money by breaking out the concrete yourself with a small rotary hammer. Grizzly sells them for about $100 including drill bits and chisels. They work great on breaking out small areas and will drill holes in concrete like it was putty.