This is the conundrum I faced a few months back. I had the choice between kakashi or minato and I based my decision based on this thought process:

If I go with kakashi susanoo, yes I could make a killer combo with jonin minato. However, I saw him as a ninja that takes up a position in your team that could have been given to a more versatile support ninja like gakido or madara. Whereas with edo minato I won't have to worry about making my mystery go through dodge because minato already does that on his own. Plus, I get the freedom of choosing an additional two ninjas to build my team instead of getting just one with the susanoo kakashi and jonin minato team (since you will always have to pick susanoo kakashi to make it work)