My personal feeling is that for the price, I'd rather go with a category 7. We always book on deck 7, so we're essentially getting a category 5 with an enclosed verandah, but the savings ends up being about $600. I don't feel like the view is that obstructed, but again, that's just me.
If you're booked in a category 7 and are worried you won't like it as much as your previous category 6, check to see if rooms 7120, 7620, 6134, or 6634 are available. These are booked as category 7 rooms, but were previously category 5 and 6. They were re-classified due to the fact that there's a slight obstruction. They do offer a much less obstructed view than the standard category 7's. We shoot for these now when booking.