You should probably shard your dataset in parts that are smaller than 1GB each 
This is convenient especially if some people just want to download some parts of it to run some tests for example. This is also convenient when building a distributed processing pipeline.
I mentioned the JSON Lines format, which is not exactly JSON: it is one JSON object per line in your metadata file. This is a nice format  But if you want to use csv or tsv instead feel free to do so