Definitely BI, looks a good size for her age. Mine have been in around 2.5' at a year. I would go to small or large adult mice every 14 days before I'd offer a rat, but that's imo. I offer mice until they can take weaned rats with little to no bulge, which ime has been at the 3' mark and 1.5-2 years old.

I don't feed my boas weekly at any point in their lives, 7 days is a bit too often. It won't kill them, I just notice better body tone when I feed every 10-14 days for the first year.

I would definitely feed f/t, boas are not picky, and feeding live is an unnecessary danger to the snake. An untreated bite, if you don't detect it, could become infected, and potentially cost their lives even if the prey doesn't cause much visible damage. Plus, there is nothing you can do to prevent the injury or death of a snake eating live prey. You can reduce the chances and possibly severity of damage, but you can't always stop it. My bp bore the scars of multiple unseen rat bites over the 5-6 years I fed him live. The largest scars he had were two knots on his neck where a rat bit down hard mid-wrap. I could not uncoil him without receiving major rat bites myself, and could not free the rat's teeth because he was squeezing so hard into the rat. All I could do was watch and hope he was ok. I finally made the choice not to put him in any more danger after a particularly aggressive rat, and it took 1.5 years of constant effort and creativity, but I did it, and he ate f/t for the rest of the 7-8 years of his life. Some snakes may be stubborn, but I'm willing to bet even the most stubborn can be switched with enough effort, and it's in their best interest to do so.

Red lights are ok as day time heating, but not preferred over a normal white light. I would either change it out for a white light on a timer, or replace it with a CHE that can be run 24/7 on a thermostat. If you continue to use a light for day time heating, you will need a secondary heat source such as heat tape/pad to heat during the night. Any light you can see, the snake can see, and it will greatly disrupt their behavior.