It is very cool to be there, and your right it is very loud! Views from the stadium are outstanding as well, most of the walking areas are covered outdoor areas on the individual floors.
I believe I saw the roof close once a long time ago, ummmm I think it was after a few $9.00 beers...the memory is vague, it's usually either been open or closed when I got there, depending on the weather.
We have a grand time when we go, we pack our little ice chests with food and refreshments (very high prices inside the stadium so we limit our purchases) and the bus gets there about 4 hours early, we walk all over to the local pubs and shops, if there are giveaways we go in to the stadium, get them and then get stamped, take our treasures to the bus and then take off walking again. Seattle is an amazing place.
I love the street musicians most of all. And sluggers our favorite bar.
There's also a Coyote Ugly type place we go where girls dance on the bar and bras hang from the ceiling