I'm replacing the fork on my bike, since it's been bent in a collision with a car.

While I'm at it, I was thinking about switching to Threadless.
Since my quill stem is fixed at 45°, and I've always wanted it to be lower.

Which of these options seem best to you?
In cost, convenience, performance...

1. Buy: threadless fork + threadless headset + threadless stem.

2. Buy: another threaded fork + threadless stem adaptor + threadless stem.

Currently the fork, headset, and quill stem on my bike are the 1" size.
I'm not sure if I need to stick to the 1" size, or if the headtube can accommodate switching everything to the 1 1/8" size?

Thank You!!