XC1 still holds a special place in my heart. It was my 2012 GOTY.
2 starts off a bit meandering, but quickly hits its stride.
3 may well be the best yet in the series. I have all three, but am finishing a play through of 2. 3 is likely to be my 2022 GOTY.
Bonus question: Yes, I would like to see a Xenoblade Chronicles X2. Maybe that could be the series' next project with the original trilogy concluded.