I ride my bike when I want to. Weather is a consideration but never traffic except the school run. The group of retirees I ride with midweek all live 30-45 minutes from our meet point so we choose to start at 9.30 simply because we aren't rushed. When we're off on a 100+ miles it will be earlier.
I'd never allow traffic dictate where or when I ride.
I ride my bike where I want to. Weather is an important consideration and always traffic,
especially the school run.
If doing a shortish ride I will either set off after the morning rush and try to get back before the afternoon one
OR in the summer, go for an evening ride instead.
If planning a long ride, I would probably opt for the weekend to avoid the school run on roads/commuter crush on trains issues, and opt for an early-ish start.
I'd
always consider traffic when choosing where or when I ride. The older I get, the more the traffic bothers me...