glad i didn't buy it yet
for me, it's alright so far. i know a few friends who fell for the hype and were pretty disappointed that after 2 years of delay, they still don't have much to show. the enemy ai is handicapped. they flicker back and forth and cannot seem to pathfind well at all. i don't like how you can swing your weapons through blocks either. the building seems like it had more potential than terraria though.
i'm hoping there's more content that i haven't found yet, though i'm still on tutorial planet. i hope there is actually a lot of stuff underground, right now terraria's caves seem way more interesting, with cave paths leading to abandoned mines and cool stuff.
i'm hoping that biomes have creatures generated to fit them. like a desert biome will have desert looking animal that use mainly fire or sand, not ice, to fight. right now all i've encountered were some farting barney the dinosaurs and their palette swap friends. i also hope that higher level planets have more interesting/complex enemies, and it's not just increased hp/increased damage. i'd love to fight larger enemies and bosses on more threatening planets. when the only thing that new enemies have going for them is increased stats, it gets pretty boring.
looking forward to playing more though. i'm hoping tutorial planet is just a ruse, and that there's actually a lot more (interesting) things to discover.