I don't recall seeing anything on the current account management site that I considered to be confusing.
I suppose that being able to undelete a deleted voicemail might be handy for some, but I already have voicemail sent to an email account for archival purposes, so I don't think I would really have a need for that. Plus, the original management site does have a trash bin for deleted voicemails from which deleted voicemails can be retrieved, so I am not really sure what the new "undelete" function really does that can not be done with the original management site. Or is this perhaps one of the "confusing" things about the original site? I guess I will have to wait for my management site to be "improved" so that I can see if it is less "confusing".
The mobile version is what I suspect triggered the redesign of the management site, and that is happening to a lot of sites these days (the me too syndrome is pervasive).
The only change I have seen so far is not with the management site itself, but the initial login page now almost immediately gets a reduced functionality (AKA less confusing?) JavaScript overlay that actually eliminates a very important security feature; the "new improved, less confusing" login page no longer has an option to not remember the last user name. The option to jump to a specific section of the management site has also been removed in the "new improved" login page (I guess that is also a new "confusion reduction" feature).
Here is the old login page:
Notice the option to not remember the user name
Here is the new login page:
Now, the user name is always remembered
And it is not just a cosmetic error of forgetting to show the security option; if you have JavaScript enabled (which is required for the rest of the site), the login page is no longer as secure as it used to be because the user name is remembered.
I have found that if I remove Vonage from my NoScript whitelist I can still get the original secure login page to appear, but then I have to temporarily allow JavaScript for Vonage after I get logged in before anything really works inside the management site, and that is a PITA.
I strongly suspect when the "new improved" cell phone style is applied to the rest of the site, I will find similar "upgrades" that are actually downgrades.