I think the fact that men automatically have the "upper hand" when it comes to physical strength puts us at a disadvantage
That's true in a one on one situation, but in social situations it might be the opposite. This video is a good example. They may not have the strength themselves, but they can get it by proxy.
however, most men would not actually take advantage of that.
True. It doesn't make biological sense to want to harm a female unless we perceive her as threat to ourselves or our loved ones. Unfortunately, a lot of things can happen in our childhood that change that perception.
Unfortunately since it's impossible to know for sure sometimes until it's too late, we have to judge men on their personality traits and hope that there is no chance that they're a sociopath or just a total creep. A man who displays too much machismo is more likely to be aggressive in our subconscious minds, so therefore a lot of us shy away from that type of guy.
I can sympathize with that. When we are sexually attracted to someone it's sometimes hard to be aware of such things. Sexual relationships always have some risk, for both genders. Women have more risk but are rewarded with more pleasure (multiple orgasms) and comfort. Men have the upper hand and less risk but are also rewarded less and have to do more work. You get what you pay for. But society skews all of this to some degree and sometimes destroys this balance, and also makes some people evil.
It's a blend of genuine self-confidence and yet humility and kindness that we seek. I agree with you that we want to feel safe, yet excited. It's not an easy balance to achieve.
As for the balance of making a woman feel safe and excited, i think that's the key to maintain a relationship, but all the stress, competition from other men and societal forces make it very difficult to do so in the modern world.