It depends on what time your ADR is and who your server is, to be honest.
7:35pm may be perfect, so long as they're running on time. A few years ago we tried Cali Grill for the first time. We booked late and our usual Narcoossee's was all booked up. It happened to be the year that Cali Grill was refurbished, so it opened late and we were able to snag a Christmas dinner ADR.
We booked it for 7pm, knowing that Wishes was at 8. We figured we'd be done by the time the fireworks started.
We were placed in the back room, next to a window, but looking out onto Bay Lake. There were two other parties in there. We were obviously a little nervous, as we wouldn't have a view. When the server finally came, he explained everything. He was so personable.
He smiled and goes "first time?"
After we smiled and nodded, he laid out the details, explaining that no fear being in the private room. They open it during crowded times. He said "everyone wants a window seat looking at Magic Kingdom. Personally, you guys have the best window seat. When Wishes starts up, you're free to head outside and view it from the deck. But, in a few minutes another... park... will be doing fireworks in that direction."
What seemed bad at first wound up being pretty cool. We were far away from the hustle and bustle outside and the room was quiet, making for an awesome dinner.
Anyway, our server timed everything perfectly. We finished our entrees by 7:45pm, at which time he returned to the table and took our dessert orders. He scurried us off to the desk, telling us that everything would be ready when we returned. Upon returning, we had a fresh table cloth, new place settings, dessert was on the table and he was pouring the last cup of coffee. "Just in time," he said.
Now THAT'S the kind of service you expect at Disney.
As far as the viewing area, it doesn't feel too crowded. It's a lot larger than it seems. Many people will run to the end to try and grab "prime viewing" but we did just fine along the rail closer to the restaurant. They do pipe in the music. The only thing I'd say that detracts from the experience is seeing the fireworks, perceptually, over Space Mountain. In MK, everything appears over the castle, but seeing it from that angle and height, you realize where the fireworks are coming from.