In June sunset is later than the closing hours but if you come in late summer you should be able to get a sunset type shot. For the Northern Lights, that is something you see at night and you have to depend on serendipity to be working for you.

I had booked the tickets online so I had chosen the time which was convenient for me which was 10 am. It is better to book the tickets online as it avoids the hassle of waiting in the Q as well as your spot is confirmed when you have booked online. You show up at Banff Gondola. In the GPS you can type it exactly the same way, it will take you right there. The walk to the Observatory is excellent and offers even a better view from the top.

We saw no dogs on the Banff gondola. The website probably has a live chat agent who can tell you for sure. You are extremely high up on the mountain and can walk up even higher, so I wouldn't recommend it. I got dizzy and short of breath because of the high altitude.

Our ticket allowed us to go both ways. Up and down.

Yes. Maximum seating in a gondola car is 4. Notwithstanding the covid19 measures, they would most likely split your group up anyways

Did not see any pets when we were there. Not sure. You could call them.

Yes they are open and book the Northern Lights package which pays for gondola ride up and down and great buffet meal at the restaurant at the top

The hike up took us about 1 hour 45 minutes, 2,319 ft. elevation gain. I would think that going down would take a little less time. It's a moderately rated trail with switchbacks to make it less steep. Nice views as the forest opens up under the gondola. You can hike it down from the Gondola's upper point.

We got an earlier departure - it kind of depends on the number of people at the time you're there. Suggest you go and try to leave when you want.

Not sure of the operating schedule. It was a great ride up the mountain. If Heights bother you sit where you can just see the Mountain.