The main thing that it has going for it is that it's a truly charming game. It's lighthearted and playful and funny. The author isn't afraid to throw in anachronisms or pop culture references just to get a giggle out of the audience. It has a time travel subplot that is much more Doctor Who than Twelve Monkeys just zany, wibbly-wobbly, and fun.
It's a short game, clocking in at maybe seven hours, depending on how thoroughly you explore and read all the flavor text. It has a good sense of pacing. It holds your interest and never gets boring. Your character progresses at a nice, linear rate; there's no level grinding; nothing ever feels tedious. It's also largely bug-free; I only found one in my playthrough, and it wasn't game-breaking.
But one of the main strikes against it is that there's truly nothing new to see here. Maybe that's actually a "plus" to some people that it just fondly recalls a bunch of very, very familiar RPG mechanics and tropes. But everything about the game is profoundly generic. It's Baldur's Gate with less complicated game mechanics, a shorter running time, and a much flatter difficulty curve. You run fetch quests and click on things to fight them. You do this for eight hours. And then the game is over.
There are a lot of really charming things about Driftmoon. I wanted to love it more than I did.