I found it very frustrating that CMD+TAB switches only between applications and not between windows of the same application.
If I have several windows of Safari open, CMD+TAB will show only ONE instance of Safari. I know that SOME applications support CMD+` or something like this, but not all of them, some applications have also different keys shortcuts. I usually set up my key shortcut in preferences as "Move focus to next windows" and sometimes work, but for example, Terminal doesn't accept it.
It's very frustrating, is there a way do move fast between windows? I also thought that swiping to another desktop was cool, but again, one application with all its windows can stay in only one desktop...