In other words...what is the setting or outing and conditions. We've had some of these topics and one just needs to think outside the "first aid box" so to speak. What about a small thermos as an idea...some are more liquid tight than others, but may meet your need.
As a First Aid dude, just consider whether a kit is for personal use, Patrol, Troop, Camporee, home, car, work.....so on. Then consider planned activities and conditions. Some of my tried and proven methods have been for a sub-kit if you will. For highway incidents or at District activities, I've had smaller kits within a kit, and these could be handed off to another responder if there was a complex event. One benefit to having multiple personal kits, if the same styles, is that most any Member could readily find another's kit and put it to work, in a tough spot kinda situation.
I like to see discussion on such things. Remember, IMHO, the best kits are those you create on your own. If "store-bought" kits are used, just remember my points on them.