I'd say, don't underestimate the pleasing aspects of a simple paint job. A good quality paint that's labeled for concrete will last for a very long time (I painted my basement floor 10 years ago with $20/gal latex and it'd holding up very well even though it's my woodworking shop and it gets abused). It's inexpensive, do it yourself, and you can have a new floor just by washing it and painting it a new color. It cleans easily and you know if you have any leaks or new cracks (doesn't hide that kind of stuff).
You can also paint designs if you into that sort of thing. You put down one layer everywhere, then tape some areas (boundaries, checks, whatever) then roll on another layer. Pull up the tape and you get a cool looking floor (use the blue painting tape).
For seating areas, you can use throw rugs that you can actually get clean (as differing from carpet which is a dirt and bug repository -- no a steam cleaner is not effective -- ever pulled up old carpet and looked underneath?)
Cliff