Thanks for the insightful comment. If other problems with land usage is actually put into perspective along with the factors stated above, you are absolutely right that the time may be sooner than anticipated.
Although in my case I would add the office room, so that when I work from home I have a place to calmly do things. Moreover, it is important to add to the house a nice garden for barbecues and drinks with friends ^^
Of course, a standard 3 br should have other details depending on taste. A mini office or study room etc. And yea, I love me a little garden to enjoy some greenery