Like asking which of your kids you like better. They are just different.
For a single person, driving in an Urban area with tight parking and congested streets, the 3 is a great choice. It is the most efficient of all the Tesla, quicker charging per mile traveled and greater range.
If in addition to driving around, you actually need to do something, then the X is the better choice. More space inside, convenient hatch design, ability to seat up to 7. Lots more room for the dog, able to tow up to 5,000 lbs (for short distances).
You get easier entrance/exit, huge panoramic windshield for open feeling, automatic opening of all 4 doors and hatch. Put you foot on the brake and your door automatically closes. You can open the hatch with a press of a button or fob. You can remotely open your falcon wing doors to let someone in our out, without leaving your drivers seat.
You get far greater visibility from sitting up high, you can raise and lower the air suspension if desired. On the open highway it is a much smoother riding and quieter vehicle than the 3.
If you have a profitable business, Section 179 makes it much less expensive than buying a Model 3.
Biggest thing the Model S has going for it its the stunning beauty and presence from it's design. It seats up to 7, has power hatch and doors. It is much better cruising on the open roads. The free supercharging that came with so many of them is just a delight as you plug in on the road and know that your travel energy is free. The Model S was the first full production Tesla. It paved the way for all the rest to come. Elon thanked all the buyers, as he was going to use the profits from the Model S and X to provide the experience and $$$ to develop the more mass market Model 3.
Really, no bad choices here. All are clean, powerful and enjoyable to drive.
My plan is to drive my X for several more years, then trade it in for a new Model Y. That might end up being the perfect Tesla for me as I retire and slow down a bit. Hope to get enough for the X to trade even for the Y.