[@Tangletail] Don't worry, this is isn't first-come first-served. If you've got a solid character with something to add to the team, you've a great chance of being accepted into the game. We certainly could use a lancer. As far as the turrets go, I might guide you more toward an Eyebot re-purposed as a mobile turret. I wouldn't want to see any of those MKII turrets popping out of nowhere ;). 

[@Lauder] A gunslinger seeking revenge against the Legion? That sounds like fertile ground for someone interesting. If you do start in the west, you can assume the Brotherhood around New Vegas reconnected with the eastern leadership. Several members were able to travel to the east, while others established a new base outside of New Vegas. The city itself went dark after the Second Battle of Hoover Dam. The NCR doesn't advertise the outcome and the Legion seem to have relocated the bulk of their forces, instead obtaining easier wins in the mid-west.