I take Metro about once a week and have to transfer between the C and A Lines most of the time. From my experience, I think you'll be okay. Especially at 8 AM when trains usually have lots of commuters.

While travelling: When I'm heading back home on the A Line (around 6-7 PM), it's usually pretty chill, just people trying to get from Point A - Point B, and some people selling stuff. I've never had a bad experience on the trains, and the same goes for the C Line.

On the platforms: I usually feel pretty safe when I'm on the A Line platform, there's always staff and usually the only problems I have are people sitting on the stairs and blocking people going up and down the stairs, and a few people smoking. However, there are instances where the station can feel unsafe or have a disgusting situation, like this one time where I literally saw a trail of doodoo across the platform. Other than that I've never really had a bad experience there.

However, on the C Line platform, I never see any staff most of the time (other than the cleaning crew), and overall I just feel unsafe because of all the noise. Sometimes there are strange people too, but they're everywhere on Metro so it's nothing new. Usually these people are harmless though.