Different missions plus TF-X isn't gonna start mass production until who nows when, our F35s will be operational in 2019/20. And we are gonna buy some F35Bs to be operated from our LHD. Do you expect the army to wait 10 years if not even longer for new aircrafts?! Seriously people think sometimes before starting to write. According to your logic we should leave the LHD stay in dock for 10 years until TF-X is ready if not even longer as we would have to engineer a svtol version which 'WE CAN'T. F4s will be retired in 2020 and replaced by the best stealth aircraft in the world at the moment and our F-16s will be replaced by the TF-X if it is successful.
Also how can you compare the T70 with a light utility helicopter?!