If your looking for a close to factory, but not totally Factory Rom. Then I would suggest either MikShifted G v2.1, or newSENSE RC1 SENSE 2.1. Both excellent Roms. Both are WiFi Hotspot, and USB Tether capable. Both are stable, and fast. Just a matter of which one you prefer.
If you try that many different Roms, and no WiFi on any. Something is up with your device.
MikROMs Since 3/13/11