I just watched it. I however think that any newbies watching, may get lost and not really understand it well.
If no other show is generally NOT expected to make it accessible after 6 years for new viewers, then why should Doctor Who be any dfiferent? Reward your loyal fans, worry about new ones when your ratings begin to tumble.
As for American clichés, us Brits have to put up with it when Americans do it on their shows...Upper lips gags, cup of tea, crumpets, posh bubmling idiots etc. We cope so you will too
Doctor Who may of become more internatonal buts its made for Brits first and foremost just like American TV is made for Americans first.