Yeah, you definitely want to spend what the house and neighborhood is worth. If you can do a $10k contractor job yourself DIY you could potentially make that a $15-20k upgrade value wise.
In the end you want to balance your personal taste with local real estate values and returns at the same time. Putting a $2k bath in a house in a neighborhood with $10k bath finishes isn't going to serve you well down the road unless you plan to live out your life in your current home.