Is steeper necessarily better though? One of the points from earlier in this thread was this from Barry Banana...
You get those big “2ft in front and 3ft lower” gaps because of the slightly artificial way the sight angles are worked out. But steepening up the stand and reducing the over-generous legroom would reduce the gap for a better view. It's because of the long, low lower tier and the height of the boxes that the seats in the upper tiers are detached and miles away.
In the ‘gentle slope’ of the old Wembley (I’m talking the
old Wembley) you were only a foot behind the guy in front (gut permitting) - a completely different experience.
There’s a lot more to the acoustics than just the roof but the same stadium without a roof is appreciably quieter than one with. Wimbledon is tiny in comparison. Direct sound is much more important at short distances than reflected sound at longer distances but who knows what TV sound engineers get up to there.
The point stands - boxes make stadia bigger, are more expensive, push the angle of the lower tier down and split up the fans with a ‘ring of silence’. Shallow tiers have poorer views and push the stands behind them further away from the pitch to compensate.