I agree with most everything you shared. I think the Mirage is a hoot to drive. I like the powertrain (1.2L & 5-speed manual) of the Mirage the most!
I can honestly say that I've owned three cars that had less horsepower than my Mirage. Yet, this is my first 3 cylinder car. My first car (1978 Honda Civic Wagon) had 63 hp. Likewise, the 1990 Ford Festiva that I drove for 14 years had 63 horsepower. We also owned/drove a 1989 Plymouth Colt Wagon DL (Mitsubishi) that had 75 hp for years. None of these cars every felt underpowered to me. They did what they were designed to do (provide affordable transportation).
If you can't make a 78 hp Mirage get up and go, you need to learn how to drive or shift. It's perfectly fine in my opinion. The A/C taps the power a bit, but I don't find the need to use A/C all that much. It does what a small economy car should do (affordable, reliable, & economical to own/drive).
I bought a Mirage because,
5-speed manual (never owned anything else).
4-door hatchback
40-50 mpg
skinny tires for winter roads
$10,173.53 OTD & delivered to my driveway (sealed the deal)
I've owned my 2017 Mirage ES manual for almost 2 years, & I am near 29,000 miles. No regrets!
I found Mirage reviews done outside the U.S. to be the most helpful, & the Mirage also has more competition outside the States to compete against. This would be an example of where the car critic gets the purpose of this car -
https://www.youtube.com/watch?v=8kDNJVrEJ-8&t=76s
Doug DeMuro's review of the Mirage ("Worst Car You Can Buy") just showcases his stupidity & ignorance. He's not being helpful to American consumers that would benefit from owning a car like the Mirage.