I tend to use 4-6 Spaces. It sounds like you keep one app in each Space; I tend to use each one for one task or type of work. One of my goals is to remove distractions, so I also tend to have a "dumping ground" space for windows I want to go back to later but not be distracted by now. (Articles to read later, etc.)
In OS X 10.6 Snow Leopard I had the spaces laid out in a 2x3 grid so it was easier to remember which was which than with them in a 6x1 line in OS X 10.7 Lion. For recurring tasks, I always use the same space so things are consistently in the same place.
I have keyboard shortcuts set up (in
System Preferences >
Keyboard Shortcuts) so that Ctrl+1 (or 2,3,4,5,6) takes me to a specific space.
I also run the utility
Witch to switch between windows. The Cmd+Tab behavior that's built into OS X switches between applications, which isn't helpful when some apps (like the web browser) have lots of windows open.
Witch lets you switch between specific windows. I set it up to only list windows in the current space, because the windows belonging to my current focus task are normally all in the same space, and it keeps the list more manageable.
It helps to customize the "assignment" (or lack thereof) of apps to specific spaces--sometimes I do assign an app to keep the windows together, but mostly I set the assignment to "None" so that I can have windows anywhere and not get whip lashed to another space when I activate that app. (In OS X 10.7 Lion, this is done by right-clicking or control-clicking or two-finger-clicking on the app in the Dock and choosing
This Desktop or
None. For (Snow)Leopard there are some hacks for this that you'll find if you search here.