What are the ESSENTIAL tools to do a basic strip and rebuild?
What you have is a pretty good start... specialty tools needed depend on how far you want the strip-rebuild process to go.  I would recommend the following


If you are changing your cables and housing get a cable housing cutter.   I use mine to also cut the cables but a normal (sharp) wire cutter will do that trick as well.  You may be able to get by with a dremmel tool for those cuts if you have one
Chain tool.  It you have a bike with gears, removing and replacing your chain can have dramatic effect on shifting performance
Crank Arm removal tool.  If you are going to change/repack the bottom bracket you will need to get the crank arms off
Bottom Bracket Removal tool
If you are planning on replacing (or tightening ) your cassette you will need to cassette removal tool and a chain whip
Cone Wrenches... these wrenches are needed for repacking the wheel hubs.