Here is my kit. I bought it from Home Depot, (better than any makeup traincase ever). Much more durable, light, and more storage.
The top compartment (btw my kit seperates into 3 individual compartment, has wheels, and can be locked with a lock.) contains most of my face products, i.e. Shadow pallettes, blush pallettes, concealer pallettes, foundations pallettes, pro remover, translucent powders, tinted moisturizers, eye pencils (in a clear plastic holder). and several other random items.
The second compartment contains foundations not in a pallette, random compacts like my beauty powders, blot powders, iridicent powders. Also my translucent powders I use in my set bag, they're in smaller mac bottles I got from the pro store, orangewood sticks, and my two clear plastic holders for my face brushes and eye brushes/lip brushes. The lower second compartment contains other smaller items like my pigments, several mascaras, different brands, mascara wands (of course), lip products, pencil sharpener, Altoids (amen), random eyeshadows, other eye stuff like Fluidlines, paints, paintsticks, small facecharts, bobbypins, rubberbands, nail files, mini sicissors, eyelash curler.
The bottom compartment contains all the other random items I always need, and people ask for, like baby wipes, tissues, brush cleaner, alcohol (99%), my mat, sponges, nail polish remover, lotion, small plastic baggies, a mirror, my mac bag/cases for lipsticks, and lip glosses, plus my big foundation pallette (since they discontinued the small ones, idiots!).
This doesn't include the several other plastic containers I use to carry backups of things like sponges and tissue, plus feminine products, lashes, some hair stuff, spray deodorant, first aid kit, cotton pads, and paper towels. Or even my FX kit, which is a whole other post in itself.
The huge wooden box was something I got off ebay and I use it to store other beauty items I can't carry, or don't have the room for, or just stuff I no longer want to use, but don't want to trash because its still new. I usually give it to assistants, or other MAU, or friends.
Man, I now realize how much work I have put into my career, and $$$$$. But its worth it, and I'm still never done wanting stuff. That was actually fun, hope it was informative. I think the key to having a good kit it of course good products, (mine isn't all mac by any means, I enjoy looking for all other products, even drugstore stuff.), and organization. You need to always be on your toes, have backups for brushes, and keep everything together, it will help when things get crazy. Also always look out for sticky fingers!