No, it's not odd at all. If you are close behind the bus, take advantage of the fact that the driver behind you is not likely to tailgate the bus. Occupy the space behind the bus that he is not likely to occupy. This gives you room to change your position within the lane. Do this quickly, because tailgating has the hazard of the bus stopping quickly. If you rear-end the bus, it's your fault. Then you can fall back to a safe following distance, and you have now created space between the bus ahead of you and the vehicle behind you, and you are in the position you need to be in.

You can move left and right in a lane as long as it doesn't cut anyone off. You may want to signal it. I make most of my signals with my head rather than my hands. I look back twice. This seems to be a really good way of getting drivers' attentions.

You definitely must start looking ahead for oncoming vehicles turning left in front of you. Right hooks and left hooks are the two biggest causes of car-bike collisions where the car driver is at fault. They are far greater in risk than rear-end collisions. Rear-end collisions are rare in the daylight. Ostensibly, drivers are looking straight ahead most of the time. With the increased use of cell phones while driving, this is becoming untrue, but I hope the trend reverses. If we can't assume drivers are looking through their windshields, what can we safely assume about them?