Even with a ultra widescreen monitor (21:9) I don't have a huge number of apps that sit in my menu bar. In fact I try to run the bare minimum (no need for Bartender or Dozer for me).
Here are my current apps that take up that space in the right hand corner:
Clipy - Free #
Clipy extends your clipboard. When you need to copy and paste multiple items or need to paste that item you copied multiple copy and pastes ago it allows you to go back and paste from your history.
I have it bound to command + shift + v and use it constantly. Just be sure to exclude your password manager like LastPass or 1Password from the preferences menu, best not to leave your passwords in your history.
Magnet - Paid MAS #
One thing I miss about window management on MacOS compared to Windows is being able to drag windows to either the left or right of the desktop and have snap and auto size to half the desktop (when not full screen). Magnet let's you do this via drag n drop. It also has other options to use a 1/4 or 1/3 etc and can be controlled by keyboard shortcuts.
Since Catalina you can get easy half width windows by hovering your mouse pointer over the left hand green dot button and pressing the option key where you will get the option to Move window to the Left/Right side of the screen.
Rectangle has most of the same features including drag to snap as Magnet and is open-source (free).
Popclip - Paid MAS #
Popclip is the missing thing from iOS that MacOS needs. When you select text via the mouse it pops up a little over lay above with options to search, copy, paste or add to Notes similar to iOS. Best of all it configurable, so you can add all the apps that you use.
Bumpr - Paid MAS #
Bumpr sits as an in between before you click on an email or URL. It pops up a menu to allow you to choose what browser or email client you want to use.
Amphetamine - Free MAS #
I use Amphetamine simply to make my Mac not fall asleep. A right click sets my display to stay on.
Itsycal - Free #
The first version of Fantastical was great in that it was tucked away until you clicked on it so you could quickly see the date of the month you where interested in or what's coming up. Itsycal is my replacement for Fantastical 1 that's open source and free.