Content Construction is a feature which should been includet to Joomla, but apparently the Dev-Team will not register that and it seems they ignore Communtiy wishes.
For K2 and all the other CCK. Although one has to say, they are all still in development and it is certainly still happen, but these components are currently useless.
Without the possibility to run the values of the new fields also in modules, all the CCKs for Joomla are failed. The same game for the output of the categories. Joomsuite Ressorce show the practice of Joomla CCKs - a lot of functions but not one of them cares of the "standard"-functionality we need. It is not possible to have a simple list of the category, just with "title, teaser, own field, own field and a pagination. Instead they develop a lot of features, only extremly big sites need.
Take an example of Drupals CCK in conjunction with the views module. In the article I can define fields and anywhere else i can set outputs. In the Content, Modules(Blocks), etc. etc.
This is the biggest shortcoming of all CCKs of Joomla. The issue and re-use of the new fields in modules and Category pages is not given.
For professional Frontend Developer typical # fail.
- K2 DOES DISPLAY extra fields in the content module (mod_k2_content). I'm referring to the latest v2 release.
- I don't know why you mention Joomsuite Resources - but K2 is simple when it comes to laying out the options you want for each category. This is the type of flexibility that not even Joomla has.
- Lastly, K2 is not a CCK - it's a content component WITH CCK-like features and a very powerful plugin API which altogether make K2 a lot more powerful compared to the original CCK for Drupal or any other Joomla CCK solution.
K2 handles the main problem of designers (the notorious "itemID" issue) very successfully, by defining and displaying layout options per category and per item and not *just* per menu item.
My point is: you need to take a closer look to K2. I can understand that your views mainly come from the fact that there is no K2 documentation yet and that is because the "final" stable release is to be released on July 27th. After that, the K2 team will work on proper documentation and video tutorials.