Hi,
I find the following free items a MUST have for XP11.
1. Orthosphotreal = Photreal ground textures
2. Re-Shade = Adds NUMEROUS shade effects to the sim
3. Zibo Mod 737NG = If you're into tube-liners
4. Extended Lights = Extends xplane's night lighting distance
5. Anything MisterX6 makes! = Both freeware and payware
6. Better Pushback = Pushbacks from gate
7. Autogate = As stated it will automate the gates that have this installed
8. Dataref Tools and Dataref Editor = Internal XP11 Tools
9. FlyWithLua along with frame rate stabilizer
10. FSGlobal Real Weather (Payware) = Adds Real Weather to XP11
11. World Traffic 3 = Adds AI Traffic