(data/values are from testnet, don't read into it)
getCollectionDataJSON() returns only collection info. contract_code value is fixed, but all other fields are updatable by user.
{"contract_code":"v0j0","collection_name":"RebelMint Beta","artist_name":"Matto","collection_description":"This time we got the cost in base units and decimals in the returned JSON.","default_funds_receiver":"0x983f10b69c6c8d72539750786911359619df313d","royalty_bps":"700","owner_address":"0xe4c8efd2ed3051b22ea3eede1af266452b0e66e9"}
getSingleTokenDataJSON(id) returns token data for a single token. Note: the 0x0 address denotes payment in Eth/base currency.
getAllTokenDataJSON() wraps all individual token data into one object. If too many tokens exist (like, a ton), there's a chance that this runs out of gas (and so would the next call), but we're not going to worry about that.
getCollectionAndTokenDataJSON() assembles collection and token data into one object.