There are no "docks" and as you mention, the sidebar is the replacement for that I believe, however it does not allow the placement of widgets. There is another app (not part of this launcher but can be used with it) which allows you to have widgets in a sidebar (I have a video for it as well LOL)...
As for the "pro" features, I copied these from the Play Store...
Pro Version Unlocks:
★Custom Search Text (Look at screenshots)
★Ability to hide app label in favorites bar
★More Page Transition Animations
★Vertical Page Transitions
★More Home Pages
★Custom Sidebar Theme
★Multiple other Sidebar Settings
★More Gestures
★Ability to include Hidden Apps in Search Results
★More Folder Icon Styles
★Folder Color Options
★No Ads
★Other Cool Features
I thought that I read in the thread on XDA that there was a way to lock icons / widgets in place so that they scrolled / were visible on each screen but I will have to search for that info just to be sure. I am not a dock user so I didn't worry about that. I did look thru settings and nothing seemed glaringly obvious that that was actually a possibility but if I find something, I will definitely report back.
As for the video I mentioned above, it is for an app call Appsii so if you are interested in it...
APPS - Video Review of Appsii Android Forum at DroidForums.net