I’ll have a detailed comparison in a bit… The average Mint flight will be better than the average D1 flight, at least when it comes to transcons. However, when looking at the total package, I prefer to take D1 because

1) D1 can be pretty good depending on the aircraft, crew, etc, and it has improved to closer to pre-Covid standards recently
2) Lack of lounge access is a big negative for Mint
3) Delta is better elsewhere - and D1 flights historically have been an important way I earn status on Delta