Yes it can be a pain if someone just sticks one wrong closing div in a page it can be a nightmare to find (even worse for tested tables).
The DW code editor is probably the best code editor around so there's no point in looking elsewhere as they all have less features. You can off course turn off the auto complete features if yo want and do it yourself.
As far as wysiwyg editors for css then they are all pretty poor at rendering css and CSS design structure needs to be crafted by you anyway. I use DW but never use design view and just use it as a code editor.
It's not possible with css to just place elements on a page with a wysiwyg interface because there are many ways of doing the same thing and they all depend on the dynamics of the layout. A wysiwyg interface could never understand the dynamics and whether elements should be floated, static or absolutely positioned.
The best advice is to study how css works from the ground up. It's not that difficult but you do need to think about what you are doing and apply it correctly.