First of all - Congratulations!! We hope you have an amazing time at championships!!
1. You dont need the team roster, but you will need your BOM. You will need to pass inspection again, so you need to turn it in again.
2. Extras... we found it helpful to make up a gigantic spreadsheet that has all of the schedules and every single person on it. Its a bit cumbersome and sometimes overwhelming, but it helped us fit in all the extras we wanted. I will address a few specifically.
Scouting - if your team is small, you may want to see if you can pair up with a team in your division. Someone else may have a large team, and be willing to share data & some of the legwork. Doing 88 teams of pit scouting & 100+ matches can be overwhelming for 10 kids. The match scouting is more important than the pit, so prioritize that.
Conferences - You can sometime squeeze in some of the evening (wed evening & thurs evening) ones. Karthik's is always an excellent one, and depending on your students the Hibner ones look good too. I'm putting on a presentation skills & running Offseason/Preship/FLL/FTC events (shameless plug). But if you find yourself overwhelmed, all of these are presentations that should be available afterward (or at least from the presenters).
"Wandering" - Give every member of your team some time to wander and check out some of the FLL/FTC/PTC/Scholarship/etc. Each should pick a target area (what they are most interested in) and at the very least go check that out. There is some great stuff to see, but with a small team, your focus should be on not getting to frazzled.. "having" to go to these things.
Rookie Meet & Greet - ok this is sort of another "plug"
But it provides a great opportunity to meet other Rookie teams and get some advice from some more seasoned teams. Plus its after things end so it might be a little easier logistically
PM or Email me if you want a copy of our logistics schedule from past years. I will see if I can get it uploaded and linked on our website.
3. I don't know St. Louis yet, but in terms of general logistics, we always put the main focus on our drive team. We set their schedule so that they can optimize sleep, but make sure to be places on time. After that comes our scout team/seat setup (they are usually the super early-crack-of-dawn crew). Pit crew schedule is the next most important - the pits are generally open at the same time as the stands, but you want them there right when it opens, and often they stay until pits close (though its not important to be "in front" of the line like it can be with seats/scouting setup. Everyone else can fill in/get there as needed.
4. I think the only thing not mentioned in 3 is if you are planning on going to the team social, and getting dinner for your team members.
5. I am not 100% positive, but with my read of everything so far, I don't think the 5 have to go in together. You usually sign for your wristbands outside the pits, so 4 could go in to uncrate and load in, and someone could hold the 5th wristband for your technical mentor who comes in at 7pm. That would allow you to get started and take care of logistics and some basic things first. (others here might be more certain, but from when I have done it in the past in Atlanta, that seems to be what would work in your case).
6. Again I dont know St. Louis, but one of the ways we have saved money is to have an adult go out on the first day and buy bagels/cream cheese/fruit type stuff at a grocery store for breakfasts. Your hotel reception could probably help you find a place (assuming your hotel doesnt have free breakfast). I have seen teams try and do this for lunches (bring sandwich stuff), but thats often logistically difficult - station someone with the food, need a cooler, etc... so you might as well just make lunch the "expensive" meal (unless there are some fast food places outside the convention center nearby). And then you can do something cheaper for dinner, either near your hotel or near the arena.
We usually try and have 1 all team meeting every evening, though that sometimes depends on how late things run. It helps to have the next days schedule lain out and who needs to be where when so that everyone is on the same page.
Hope that helps, I'll see if I think of anything else. Drop me an email if you have any other questions