I don't think much about the subject, but I'll give my two cents: People try to be "creative" with weapons, but it's sometimes the wrong part of the story to be creative with. Not that you can't come up with new weapons, but weapons tend to seem silly when they aren't as effective as the existing weapons. "Why don't they just use a sword/gun?" some may ask. It's good to be able to answer that question. Secondly, it's good to know the physical outcomes of the weapon you've designed. If it's large and has a lot of its weight distributed on one side, maybe consider making it lighter. Of course, there are weapons, such as atomic bombs, that are made to house incredible power and nothing else. But even in that case, weapons are designed for practicality, not style. Style's great to have, but I'd not let it get in the way of practicality unless you think you can use the absurdity of certain weapons to an aesthetic advantage.