I just looked up all activities for the week we are planning on going because I remember being stressed about it last year too. Here's what's happening this year: Field Hockey showcase Feb 7-10 / National high school cheerleading championships 9,10,11th / And Daytona "shootout", "pole qualifying", & "Gator duel" (whatever that is because I dont' watch Nascar) is on 9,10, &14th.
I am clear for twirlmania, soccer, & most of the events mentioned above are taking place the first weekend we get there. We will get there on a Saturday and I remember MK being packed that day last year but after that it wasn't bad. And it was not even close to comparable to summer time. We only saw cheer/dance kids when entering MK because they were in a parade. Didn't see any mis-behaving like we were affraid of. Also, last year we arrived in Orlando on the 1st day of all this Daytona stuff and didn't notice an increase due to that at all. The 300 & 500 aren't until after we leave. I'm pretty sure those are the Daytona events to watch out for mostly.
There is also the builders convention this year which they had last year. I didn't see crowding in the parks but like I said earlier, the resorts were booked solid. This year the convention will start on our last 2 days which will be a wednesday & thursday. So, I'm not too worried about them packing the parks until the weekend and we will be gone by then.
All in all I think it will work out about the same as last year. Were there lines? Yes sometimes, but nothing a fastpass here or there couldn't handle.