The Like button is a good choice. Again, you can create your own "Action" button if you wanted, instead of theirs, but I'd recommend that. With the JomSocial Open Graph plugin, you can define the type for profiles. However, by just enabling the Open Graph plugin, it will automatically set the Open Graph image tag for the profile page to their profile as well as the title (their name) and description (I think this is their "About Me" field, but possibly last status update). That's all without even creating a "Profile" object type. Some of the cool stuff our Open Graph plugins can do automatically by just enabling them
We just re-built the EasyBlog plugin with the missing files and did a quick test. Everything looks good, which means we'll push it to our update server in a few hours. So, in 6 or so hours, go to the Joomla Installer - Update Manager and hit Refresh. v4.3.1 should show up there, update, and work without a hitch.. hopefully
As for categories, the category you select will work for all sub-categories. So, just select a main parent category, and you should be good to go. Then, if you, for some reason, don't want a sub-category to have the action applied to it, just create a new object for that specific category and don't assign the action to it. It's flexibly confusing, is the term I think we're going to call it... the biggest issue with EasyBlog or K2 is that the category drop down doesn't show the hierarchy. Something we will be adding, but right now, it's a flat and confusing list. Enjoy!
Finally, a Kunena specific plugin is something we'll create just for the "I posted" action. However, for the auto-post on read action, you'd need to mark all your posts as "article" since the news.reads action only works with articles. If that's something you'd want to do, you could actually do what you're looking for right now with our Custom Object plugin. Create a new Custom Object and add the following parameters:
option=com_kunena
view=thread
Then, give the Object type of "article". I'm actually not sure of the view=thread thing, just giving you the idea, you'd have to know their non-SEF structure.. but that's the power of the Custom Object plugin.. you can now assign an object-type to any extension, even if we don't have a specialized plugin for it. The specialized plugin would just add some new specific features.
Hope that helps explain, as always, but if not, keep us posted on what you need! Loving to see that actions are being created and submitted and, most of all, WORKING!
Best of luck,
Alex