kitty vs Ásbrú Connection Manager

Very elegant keyboard shortcuts for creating and navigating between tiled terminals within each tab with no appreciable lag.

Supports plugins to add features one at a time for those who need them. Examples include Unicode input and side-by-side diffs.

Operate several terminals from one window using the tabs feature, allowing you to make simultaneous connections to different remote hosts.

Allows for viewing the scrollback buffer in an external pager of your choice ('less' by default, with support for 'more' and 'most'), a huge benefit for turning actions taken in a live terminal session into a script for efficiency or dissemination or collaborating on workflows.

No graphical menus to clutter the screen saves system resources and time once you learn that all those options are still available from the command line within the app.

SSH1/2, Mosh, FTP, SFTP, VNC, RDP, Telnet, Serial, WebDAV, and IBM 3270/5250

Very active project on their GitHub page with a lot of interactions from all over the world.

Groups and subgroups can be created, and connections put in them, to organize a large amount of connections so that you can get more done with the program
If you were looking for this feature from SecureCRT, it's here

Authentication credentials and SSH keyfile passphrases can be supplied by KeePassX rather than being saved in the application's settings.

Easy access to the local machine's command-line interface is provided by a dedicated tab shown adjacent to the tabs for all remote connections.

All terminals have a command history of some sort, but this is the only one I've seen with a panel on the side that lists it right before your eyes, and allows you to click on any command you see there and have it instantly filled in on the current prompt line for revision or re-execution.

Use different proxies for different simultaneous remote host connections if desired

Most actions that can be performed over SSH can be scripted and set to run on a schedule, automatically upon connection, or in response to a received message or prompt.

Built-in support to split a single tabbed connection display into upper/lower or left/right halves as well as quartered. No need to use tmux, screen or the like.

Application can be minimized or closed to a tray icon to free up taskbar real estate during background operations.

Offers the ability to send a properly formatted "wake-up" packet to a device in the event that it is powered off so that a remote connection can be established.