Currently, several of the query parameters for the delivery endpoint require the use of characters that are not valid in a url and therefore must be encoded.

This makes the feature harder to use for developers. It is a pain to need to url encode the characters. 

it also makes code less transparent and harder to understand.

It also makes the documentation more complicated.

Here are the allowed characters: (PLEASE DOUBLE CHECK THIS)

 - _ ~ .

Are these usable?

$ - _ . + ! * ' ( ) , 

For discovery - check the Delivery endpoint - identify all cases where non-valid characters are used - and propose some replacements. 

Example:
[like]=something% → ENCODED → %5Blike%5D=something%25

Proposal: (like)=something*