Ah, yes, Emergency Kit is a great idea. Two essentials (if you ask me) are sewing tools and a glue gun (and sticks, of course). Between the two, you should be able to fix anything, if just temporarily for the weekend.
And as for the Friday line, it actually can get pretty lengthy. LAst year I showed up around 4:00pm, I believe, and the line was already a couple hundred people, split into two to four lines. So, yeah, the number of people who take the hint and pre-register grows every year. The first year I attended (2006) the pre-reg was only like a hundred, but it has boomed massively since then.
So yeah, the line can get pretty long, even on pre-reg. The earlier you can get there, the better.