1st issue is that strongholds, spawned, villages, temples, etc. spawn without any chests/loot. All of the structures that would normally have chests or loot, have none.

Second issue, is that on the seed 1669320484, there is a never ending ravine, created by multiple ravines generating next to each other every chunk. Same thing happens with certain patches of trees, where it constantly repeats. Or any structures, etc. 

 
(See below pictures)