Have at least 2 separate circuits for outlets, and perhaps a dedicated one for high-current items like an iron. Lighting should be on different circuits than wall outlets (all this is building code). You may need to have your electrical service upgraded for the additional circuits.
Use a lighting modeling software package to make sure you have adequate lighting in all areas. Use high CRI (color rendering index) bulbs in all light fixtures (>90 CRI). Watch your color temperature on the bulbs (5000K+ can feel like a doctor's office, below 3000K might feel too yellow).
Why in-floor heating? Is this on slab? Make sure the vinyl is compatible with it (in many cases, it is not). Do you have any other HVAC planned? If not, consider a mini-split heat pump.
Are you adding a half-bath? If the plumbing allows one, consider it.
Be sure you pull all necessary permits. Use licensed contractors. Take photos of framing/electrical (with reference markers) before things are insulated so you know where they are.