The KSP_x64.exe will never completely terminate, because this - the last entry in the log:
[EXC 02:17:51.635] NullReferenceException: Object reference not set to an instance of an object
KSPPreciseManeuver.PreciseManeuverToolbar.OnDestroy () (at <148a8ec2de454d9cbd6a3d0df7bebbc1>:0)
UnityEngine.DebugLogHandler:LogException(Exception, Object)
ModuleManager.UnityLogHandle.InterceptLogHandler:LogException(Exception, Object)
UnityEngine.Debug:CallOverridenDebugHandler(Exception, Object)
The KSP_x64.exe will never completely terminate, because this - the last entry in the log:
The process still needs about 400 MB RAM then.