The 3.8 core version of the Advanced Image options provided 2 fields for margin, horizontal and vertical, and when you entered pixel values in those fields, would display those values, written as css, in another editable field. In that field you could extend the statement by differentiating left from right and top from bottom. I taught the users I support to write margins as
margin: toppx rightpx bottompx leftpx; They got that. One could also add padding (say to create a white edge, like a photograph, pre-digital) and very specific border info, like color and style and thickness, per side.
While the new plugin does offer 4 fields for margin and a single field for border size and color, it doesn't show that editable field - so there is no ability to manipulate padding or control border by side. Acknowledged, most of the time that's not necessary, but that's always been one of the things I've loved about WordPress - it's common sense flexibility and many different ways to reach the same goal. Sure I can edit in the text editor. It just takes longer. I just don't need companies making my life more challenging; believe me, it's challenging enough.
There was also a field for changing the source of the image - not something I encouraged users to do, but often it was faster to go in and change the source code there than to delete the image and re-add it, or again to go into the text editor and edit the tag, just depended on where you are in the process. That's not included in the plugin at all.
Also the percentage scaling was a quick way to make adjustments - not perfect but quick - and often a way just to see what percentage adjustment an image needed to look right.
All that said, my broader concern is the long term prospect of WordPress developers using plugins to compensate for crippling features in the core, while at the same time exhorting users to slim down their sites by reducing the number of plugins used. The plugins I use on every site, security, SEO, etc are pretty cooperative and widely used, but I've also experienced weird conflicts and that only gets worse the more plugins you are FORCED to use.
I've been using WP since around 2.5/2.7 and especially since 3.0 was released, I've been an enthusiastic proponent, moving my clients from a mix of static sites and Joomla sites (and one renegade Ruby site) to WordPress with good results, BECAUSE WORDPRESS WAS CONSISTENT (Joomla drove me crazy with their wild veering roadmap and "upgrades" that were full-on migrations) and seemed to actually care about the needs of its users - the full range of users, from php developers and power users to moms blogging about their stretch marks (Full disclosure - I'm a mom with stretch marks (unblogged) as well as a power user). I've based my business on accommodating that range so I spend a significant amount of time in support, another reason I've come to rely on WordPress' ease of use and consistency. I understand it's not the WP developers' responsibility to consider my business model and mental health but I would submit, based on the consternation I'm seeing on the forums, that it isn't just me.