It would require a bit of work to get this up to the standard of something which could be used on air, but it is achievable.
It would help, as
mentioned, to use the correct typeface if you're able to (in this case, BBC Reith).
Then I would look at the sizing. Think about the viewer - the text size is currently rather smaller than I'd suggest. If you take a look at the real BBC menus/on screen graphics in general and use that as a guide, you might find it easier.
I would think about the alignment too. Each slide is a bit different. You should be aiming for a bit more consistency and I would suggest creating one template and then editing the colours/logo etc thereafter to keep everything a bit tidier and more consistent with each other.
Also, a brief word to
(above) - it's very easy to write a snippy comment on someone else's work, but having looked at your Gallery and found two mocks (both rated one star), perhaps you should consider the irony of the situation and think before you write unnecessarily harsh and entirely unhelpful feedback in future.
Guess who's big in the back time!