You can have multiple ssh config files, with includes, to keep the configurations structured and organized, and not one long dump file, then use any gui terminal app that supports tabs. And tab+auto complete hostnames from the said configs. Some apps also support something like multiple profiles, so you can put there your ssh <host> command, if you want some gui lists. I follow this approach and it is very portable, as the only thing I need to care about are my config files.
You can have multiple ssh config files, with includes, to keep the configurations structured and organized, and not one long dump file, then use any gui terminal app that supports tabs. And tab+auto complete hostnames from the said configs. Some apps also support something like multiple profiles, so you can put there your ssh <host> command, if you want some gui lists. I follow this approach and it is very portable, as the only thing I need to care about are my config files.