This is somewhat controversial, but the strategy that I've seen work best is to make your first priority to have a competent debater as the second speaker. This means you don't always "play to the strengths/personalities" of each individual.
If you have two debaters and one is a novice who has trouble in BOTH positions and the other is someone who has enough competency in both, have the better one be the second speaker both ways. Why? You win rounds in the rebuttals -- if your 1NC flops, you can pick up in the 2NC. If your 1AR flops, you can at least do some crazy weighing to cover the drops in the 2AR. The judge often remembers the 2AR better than the 1AR. It doesn't matter if the novice is more big picture and the competent debater is more line-by-line oriented -- plug the 2_R hole first. Time and again, teams put the competent debater in the 1A slot because of the 1AR. They win the 1AR, then lose the round because of the 2AR. On the other hand, teams that put the competent debater in the 2AR are often able to say "look, we dropped a ton of points in the 1AR, but they don't matter and here's why." Same with neg: the 1NC is the scariest speech of the round, but if the 1NC has two weak points, the 2NC can either extend them and make them strong or bring up new points (because it's still a constructive), watch a weak 1NR follow, and then win in the 2NR.(side note: I'm not saying the 1_Rs aren't important; our team definitely won rounds in the 1AR and 1NR before and I consider the 1NC and the 1AR to be the hardest speeches of the round. Winning in the 1_R, though, is often the exception not the rule, at least in my experience)
(tl;dr: my personal experience is that if one debater is bad and the other is not, one should put the bad one as the first speaker)
If you have two fairly competent debaters, both of which can handle either position, THEN you figure out individual strengths. Generally, you put whoever is bigger picture in the second position and whoever is more detailed (and often on neg, faster on their feet) in the first position. Again, this is because you want the 2_Rs to be big picture and weigh the impacts of the arguments. Also, the 1AR and 1NC are often very line-by-line (the 1AR especially), which means you put the more detailed person in those positions. The 1A also should ideally be able to talk fast and have good word economy, because of the 1AR. Also, if one person knows theory and the other doesn't, the theory person should be the 1N, because pre-fiat arguments are usually 1N arguments.
At the end of the day, though, no theory fits your situation perfectly. You should definitely experiment and figure out what works best for you