What's the Drupal 8+ replacement for CTools content_types in D7?

In Drupal 7 CTools had the concept of "content_types".

We loved to use them as "Blocks on steroids" ;) for a project, where we especially needed the following functionality:

• Provide "Components" with options, which could be placed in several contexts, for example panels or as blocks etc.
• Expose these blocks to Homebox for end-users (defining the settings for each instance in their homebox)
• Use context keyword substitutions (would be Tokens today) from the context where the component was placed

Drupal blocks already allow defining a settings form, but there's no concept of using substitution from the placed context yet, I guess?
Furthermore, I'm not sure, if blocks are correct to be used in Drupal 8+ where content_types was used before.

TL;DR: So to sum things up, my questions are:

1. What happened to the concept of CTools content_types and is there anything comparable for Drupal 8+ in core or contrib?
2. Is it correct to use blocks for this instead and would it make sense to find a way in contrib to use tokens as dynamic block settings from the context? (e.g. a node, user, ...)

I didn't find any documentation about that. Read this a general discussion, I'm just interested while working on the upgrade of the affected Drupal 7 project.

Thanks :)