Please, there is a bunch of difficulties, such as not being able to move a sub connection into a folder, or a connection into a connection to make a sub connection.
You have made the differentiation between a folder and a connection, but then you have also added sub connections.
Sub connections have the option to reference their parent information, but a connection in a folder doesn't have the ability, even though the parent folder has things like IP address and username.
I think that you should get rid of the folder and sub connection option, and simply move to a labeling system. If a connection can have more than one label, then I can organize it better, not only can I organize the way that I want, but I can quickly and easy Filter those labels to get a different organization.
E.g. I have a server, call it SRV001.
I can connect to it with RDP, VNC, SSH. and it is part of the crazy.local domain, at the building 1 site.
I can make three connections, RDP VNC, SSH, and label them Crazy.local and building 1
Today while I am working on updating servers in the crazy.local domain, I can filter for that label.
tomorrow when someone from site 1 is having issues with that server I can filter for site 1 to find it easier.