Yes, there have always been foreign riders, so there must be some system in place.
I agree about the replica issue. When the lovely Olie won last year, noone got a rep, and it would make sense to change the system, as getting a rep is the only reward a rider can aim for. If not the top 50% then perhaps within 120% of the winner (I think it's within 110% at the moment?)
When I first came to the Manx, there were no sponsprs (well, officially!), and the bikes were considerably different from those at the TT. Nowadays, many of the top guys have bikes capable of winning the TT, and yet we still have others on elderly bikes incapable of keeping up no matter how talented the rider.
Speed is one thing, skill is another. I deplore the current obsession with lap records. The great Bob Mac always said "Win at the slowest possible speed". That's skill.