I've put some thoughts below with references to cookbook recipes, I'm not saying they are in sweet point for a lovely resource oriented design but they are thin

I've put some thoughts below with references to cookbook recipes, I'm not saying they are in sweet point for a lovely resource oriented design but they are things you can handle. 1. Recipe 2.4 is one option. Alternative might be granular resources, if the characteristics of your use case means they can be done efficiently. For example we might include the URL to author details inside the article. That means another request, but if those author details are made immutable (as in change to author details means new URL), then they can be given a long cache period. Also HTTP/2 will mean more granular resources have different performance characteristics. 2. Recipe 11.10 could work so the URL would be the comments collection as a whole, I'd use PATCH (or POST if PATCH isn't an option) to then send the updates you need. So a PATCH to /<posturl>/comments with the result body including information that causes those comments to be deleted. 3. Same idea as 2, I'd use PATCH to the collection or a custom resource.