The $ approach:
No budget worries? Hardwood, with area rugs in bedrooms and wherever else I feel like. Hardwood stairs, with a nice runner if needed. Tile or lino in kitchens and baths.
Skimping a little? Carpet bedrooms, carpet stairs, hardwood elsewhere, vinyl or lino in kitchens and baths.
Just need new flooring of some kind while on a budget? Carpet everything, vinyl in kitchens and baths.
The life event approach:
First home, about to start a family? Carpet everything, tile nothing, sheet vinyl in kitchens and baths. Update it to whatever you want when the rug rats finally move out or are at least big enough not to smack their skulls on your hard floors. Maybe get some carpet back in there when you're really old and your bones are brittle.
The dust and chemical sensitivity approach: Pre- finished US- made hardwood everywhere, no carpet, tile or lino kitchens and baths, and vacuum every day + wand under all the furniture, against the base, etc. etc.