The big action set pieces I don't mind and indeed expect. Bring 'em on. All I'd like Pegg to do (and anticipate he will) is inject some character-driven humour and warmth in the 'boring-bits-in-between'.
Of course. I just think it's better if Pegg had the freedom to write what he wanted (including big action set pieces). Basically i'm saying, story first, big action second.
Taking a look at Lin's work I think he can deal with stories just as well. F&F isn't the only thing he has done, nor do I think it is the only thing he wants to be known for.
But, that's just my opinion on the matter. Likely we will have action, but with Pegg's writing, and Lin's ability to handle ensemble casts, like Trek's, I imagine there will be plenty of character moments that don't involve the action.