Make absolutely sure that you will not have any moisture problems into the future. You did not mention anything so its just a question because any moisture problems will ruin all the hard work and materials.
Definetly use vaper barrier and insulation!
If you have a washer or hot water heater near the area (even AC), make sure that any overflow will drain properly and not damage the finished area.
Make sure to provide plenty of electrical receptacles and follow code.
You may want to finish with throw rugs that can be removed to dry in case of a flood. You can take a 9x12 throw rug outside and dry it, but a permanently installed rug will get ruined. Ask yourself these basic "what if" questions.