Congratulations on your impending new addition
I hope you will let us know when you bring him/her home.
One quick note before I answer your questions: Keeping a hamster in your bedroom should be fine. But, bear in mind that they need a large cage. Don't compensate on cage size just so you can keep it in your room. Also, hamsters make a lot of noise at night: running on their wheel and just pottering around. That's fine so long as you don't mind and are prepared for it.
1) Dogs: So long as your hamster has never encountered a dog before, it won't know to fear them. That's not to say you should ever let your dogs into the same room as your hamster, but the barking will just be another household noise that he/she gets used to. I should stress, again, that you must ensure the door to the room you keep your hamster in is shut at all times.
2) Lighting: I think this should be fine. I have never worried too much about lighting with my hams, but I do keep them in a separate room which I don't use for much else so, by coincidence, it is light during the day and dark at night seeing as I barely ever switch on the lights in there except during the evening when I see my hamster. It's a good idea to provide a hideout so that even if you switch on the lights, your hamster has a dark place to go.
3) Free ranging: I have always allowed my hamsters to roam free once a day in the evening, rather than using an exercise ball. They do love the stimulation, but it certainly doesn't make them unhappy to return to their cage. So long as your cage is large enough and you provide enough toys, they will enjoy being at home too. However, make sure that the area you use for free roaming is entirely hamster proofed: no wires, gaps or furniture to diappear under/behind etc. And don't use chemical cleaners in that area. If you don't have a suitable space, your hamster will be happy with a spacious playpen.
4) Music: Without being in your room to hear how loud the music is from there, I can't answer this and we don't play music often in my house so I can't answer from personal experience. But, I think if it's on a separate floor and since you say it is faint, it should fall into the catahiry of general household noise which will gradually become background to your hamster. Having said this, you might want to keep things quiet for a few days while your new pal settles in to avoid stress.