1. Alright. The scifi setting has a lot of alternate canons anyways.

2. They could have helicopters if they didn't want to make use of anti-grav technology for some reason. Such helicopters would be rare but there would surely be one or two models still existing.

4. That would also be like Cloverfield, sort of. The smaller baddies is good to have. This makes it seem good if they were sentient at least somewhat so you can have a character among them.

5. Could happen.

6. I tried out that idea earlier but not through planned battles so it took a long time and then died. I wanted to go through all my characters who haven't gotten a chance to fight yet. Some battles could have multiple of my characters teamed up with others are more one on one. They are fighting a group of bad guys called the Big Bad over a period of time if all the battles will be the same canon. If we are going for a long running battle, that plot actually strikes my fancy better then the monster battle over a lot of battles.