And now, i found a good Slackware-default software (Huh, if i being in that way, i make review on every program in Slackware :D), it's window manager, called WindowMaker(wm), and i want show you reasons, to try it's.
If you read InstallGentoo/Software_Minimalism, you can found, that WindowMaker is recommended as minimalistic window manager, and also it's included in Slackware by default, it's can make your system setup more fast and easily, Windowmaker is have a lot of theme's (My favorite are Autumn and Black), graphical utilities, bakcground-image support (Minimalistic window manager's don't support that function's, you need install feh to set background), and retro-like style, the only problem, that i found, it's lacks of hotkey's function's (To add new hotkey function's, you need to add command to context menu), but i install sxhkd and add hotkeys for volume control (Now i don't use sxhkd, i just control volume in applications directly). But, with standart set of hotkey function i setting up my system like i3wm-hotkey's.
On that page you can found a lot of "dockapps", it's program's, that look like native window block's, and show you some information or function's, you can get sources of them with one command: git clone https://repo.or.cz/dockapps.git. And, you just need to run yourself, or add to autostart in .xinitrc, all of them have the same style, that can give more harmony on you'r desktop.
I use i3wm almost all time, that i use GNU/Linux, and i have some troubles with non-fullscreen applications, like xmms, or Pidgin, who interface is being too big in full-screen, or any other software, that can't be opened in fullscreen, here all my programs is felt comfy.
So... I think, that is the best floating window manager, and after stacking, it's not so scary, as i waiting for, i also discover, that WindowMaker/GNUStep have pack of programs, like eMail-client, Terminal Emulator, Audioplayer, and Advanced WindowMaker plugins for icons on Desktop and Dock,and all that can be combined, but i don't need this now. Really, i think, more minimal can be CLI-only. I think's about try some time working without X, where i don't need it, or just start it in other TTY.