What about long trips though? A bigger car is generally more comfortable. More room for luggage, etc. I recently fled from Houston right before Harvey hit, and I put my two cats in their individual cages, a litter box, my suitcase and tons of supplies and had room to spare. That one trip made me love my S an order of magnitude more than I already did. That was the first time I used the frunk, and since my car is RWD I have a large frunk. I'm just afraid I'll miss all that space if I go for the 3. I also drive a Volt, and I do like the smaller car in parking lots.
Based on your reasoning just go for the X!
7 people and whatever cargo you want up to a 747.
Bigger car is more flexibility but the 3 is way too awesome for being half the price of the S.