When comparing Plank vs Ulauncher, the Slant community recommends Ulauncher for most people. In the question“What are the best Linux app launchers?” Ulauncher is ranked 5th while Plank is ranked 7th.
Ranked in these QuestionsQuestion Ranking
Pro Simple and minimal
Plank is a good choice for those looking for something simple that just does its job well. There is no UI for options built in to the dock as to change anything those options will have to be accessed through a text file.
Pro Third party themer available
An additional third party app has been developed that allows theming the dock without the use of any extra resources. This is great for those that are not using elementary OS and the elementary tweaks extra.
Pro Solid and light weight
Pro Supports extensions in Python
Pro Able to launch Kdialog, Zenity and Bash scripts
Extensions are easily created. Python script is all open to see. Not compiled like some.
Pro Supports fuzzy search
You can enter app name with a typo and Ulauncher will still be able to find it.
ULauncher supports themes and comes with a good supply on install but more can also be made.
Pro Allows custom shortcuts
Con Poor workplace awareness (cycling windows)
When configured to only show apps on current workspace, cycling an app open on multiple workspaces will switch workspace focus, update the dock and often leave you to cycle another app.
Con No right click menu for some apps outside of elementary OS
Other file explorers and terminals (those not found in the default elementary OS) do not have any right click menus for the dock meaning it is impossible to launch multiple windows for certain file explorers or terminals.