cynematik,
Before you start giving up on what this plugin offers, please review this page FIRST: https://wordpress.org/support/topic/ricg-responsive-images-moving-to-wp-core and THEN, see if someone else has already started a Support Forums Topic that addresses your individual concerns. If not, start a new Topic and I’m sure one of the developers will do what they can to help you out, or make recommendations.
To prepare for this plugin’s merge into the WP Core, a lot of thought and effort has already been put into this by both the Plugin’s Developers and several Core Developers. Whether you install this Plugin or not, its components will become part of WordPress 4.4 Release during the first week of December. Your request for help or expressed concerns posted in the Support Forums can actually help develop better components for this in the WP Core.
+1 for the great comment by Shapeshifter 3
We all have to deal with the increasing variety of image sizes and your experience can help a lot.
Here is a conversion about Responsive Images: Post Status podcast (9th of October, so it’s very new). Brian Krogsgard and Joe Hoyle talk about this concern as well.
AFAIK, this plugin does not create any of those image sizes, it merely makes the existing sizes available to your browser, so the browser can choose the best image for the viewport and device size. WP creates 3 image sizes by default, and any others are the result of your theme and other plugins.
