The 8.0.2 TSP was originally released with Unity 4.1.1 as ENU-only. A couple months later a multilingual version of 8.0.2 was released. Other than the additional install languages there is no difference between the two. Hopefully it is obvious why the ENU-only version is much smaller than the multilingual.
The 8.1.1 TSP was released with Connections 1.1.1. I haven't looked at what's on CCO but possible the smaller size here is again because it is ENU-only. With respect to features and bug fixes, 8.1.1 has everything that was in 8.0.2. Plus it has everything that you see in the 8.1.1 release notes.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.