1. I don't know any way to get easy overview of the start and end times of your flows other than putting them in your calendar or some excel file. Or having the flow send you notification whenever it starts and stops.
You should keep in mind that Desktop flows can't start at the same time on the same machine. So they are not going to mess with each other. If you have one machine the desktop flows will run one at a time.
So recurrence cloud flows start at the same time and they both have PAD flow in them the latter one will be in que and start after the first one has completed.
2. Again I don't know a very clean way of doing this.
You could have for example an excel file that has cell being 1 or 0 (ON or OFF). The flows could update that value. So everytime automation starts it first updates the value to 1 and at the end change it back to 0.
Then another flow which you want to be running as often as possible would start every 5 minutes and check if the excel cell has value 0 (OFF) and if so it does its work. But if it has value 1 (ON) then it terminates flow and tries again next time it runs.
You should also think if it is actually important for the processes to be running all the time.
It's not very productive to have bot to be running just for the sake of it. There is also a risk that some flow gets stuck and important flows get pushed back.
I haven't used work queues myself but maybe those could help you also.
