I can't believe people failed to mention a few things. First off, any survival gear kept in your sled needs to be deemed useless. You need to keep it ON YOU. If you need to spend the night there is no gaurentee you will have your sled, things can happen. People have fell off cliffs and only have their pack to spend the night with, worst case you need to plan for. And EVERYONE needs to keep their OWN stuff. Second off, NO it wouldn't of been better to send one of the kids off with the sled. You NEVER EVER split up, ANYONE, no matter WHAT. And, your best rider is ALWAYS LAST, the 2nd best will lead at the worst times. And the biggest mistake is, clearly your experience is low, you shouldn't be the most experienced person with how much you have in that kind of conditions. My group, we will push the limits of the least/lower experienced riders but that is it. If it's a new area no one knows we are a lot more careful. It is always the way to do it.
You survey the conditions, if the drift is to big you stop and shovel. Even an hour spent shoveling, it doesn't matter. Your on a trail and you know where you are it doesn't matter if your there well into the dark.
What I would of done after you got stuck. First I would of surveyed the 1st stuck 90% chance a bit of shoveling and lifting it would of been out, if 6 guys can lift it out instantly, I could free it myself in maybe 20-30 mins no problem. Even if it couldn't, you work to free the other two right away and don't waste time on the 1st. And I mean turning sleds around on a trail? I've done it myself plenty, and my RT1000 isn't light. You ride one and then two boys double up behind, with a broken trail it is no problem doubling up.
I will not hesitate to ride in deep/hard snowing conditions with only 2 people. I know almost anything I can get a sled out with only 2 people. However, if there is a lack of people later in the day due to exhaustion and if daylight is a facter I will watch it and not get the sled stuck to badly. But you should NEVER have more then 1 sled stuck, so you could always double up if you need to.
The ONLY time my group has ever split up on purpose was when I snapped a chain we left my sled and drove the trucks in part way. We only sent 2 sleds and 3 people to go back in to get it. But 4 people left at the trucks know to come back in if the others don't return in a reasonable amount of time, plus the conditions/daylight were fine. It just didn't make sense to send 6 sleds and 7 people for 1 sled.
I would highly suggest you get some more mountain experience before you try to lead another group. I consider myself decently experienced, and wouldn't feel comfortable without atleast 1 more person with my experience atleast, much less 2 people with almost none relieing on me. And I know my mountain riding experience is quite high. And I also have a multitude of survival gear(one of the biggest packs, 50L I believe FULL), and a avy course (you don't ride with me without one, or VAST knowledge).