In KDE Plasma, if you right click on the launch menu button, there is an option Show Alternatives. Here, you can immediately select and use one of the installed alternative start menus. On top of that, you can install further launcher menus, which will then appear in the Show Alternatives list. I installed Simple Menu (from Eike Hein) that has categories, favourites and search. And let’s you move the icons around. But its that easy to try out different launchers. I hope you find a good one.