Inded, the busing at the airport is very unpleasant. I understand that some airbridges still need fixing. Not TG fault.
However, I am surprised by the comment on immigration. I am also sure that TG did not have dedicated immigration lanes for Biz pax at the old airport. And I am not aware of other airports in the world (there could be a couple) where biz (not F) pax have dedicated IMMIGRATION lanes.
Security checks are another issue. Before boarding planes going to Europe in the evening, there is usually long lines at the three machines . This is a security check for all pax, including those in transit. there is no FAST track for elite, biz or F pax. so even if you are a F pax escorted by TG staff, you have to wait for 15 min in line. That is different from many other airports where there is a fasttrack for security (e.g. LHR, etc...).