I have the same worries with the 1 and 2 year old group I have. I do find the more I let them free play the more bored they get and the more the misbehaving starts. So I try to direct the play a little, Lego, puzzles, kitchen etc. We do crafts when the 1 year old sleeps, cuz she eats everything! Don't beat yourself up about sitting back, I know I do but it's a hard age to really be involved.

Vaca...3-4 weeks is totally acceptable! Especially unpaid. I work it into my monthly rate so my month to month payment stays the same however parents are not actually paying. I take 20 days, 15 vaca and 5 for sick, training or emerg pop ups. I post in February each year so parents know the schedule and how to prepare.