i literally started a thread about preferred/favorite mods yesterday, but I guess this is more geared towards "types" of mods. So, my LEAST favorite are the automation mods, my favorite are car mods.
The Dodge Coronet by @Stoat Muldoon... I love classic mopar, and when made into a dev quality mod there is nothing better
I love the mod for the classic H-Series, I also love the LKS Prerunner! And tons of other mods. The only mods I really don't like are Russian mods and the Gavril D1, because I don't like it that much.