Get a permit, any faulty work that say burns the house down can be your fault without a permit. Any resale value you think you'll get from this finish will vanish.

Get a radon test before you start.

Seal the concrete against moisture.

Put in a full bathtub not a stall.

With your plans and kids skip hardwood and use a vinyl wood product.
http://www.homedepot.com/h_d1/N-5yc1...&storeId=10051