Well, none of the problems are insanely difficult, either . Remember you have over two weeks to solve them.
Speaking for myself, I would rate BTOUR as moderately easy, HOLIDAY1 as moderate, while BLOCKS and HOLIDAY2 as moderately difficult to code. But that is just my point of view. After all, in the league the number of correct submissions (and consequently the number of points awarded for solving a task) seems to be a fair measure of how tough a problem proved to be.
There are going to be 2 challenges in this problemset - SANTA and one more challenge to be added before December 20. In both cases it will be easy to get a high score with a seemingly short and simple algorithm.
Finally, I think I should stress one thing: I do not treat coding such things as Input/Output routines, data structures (e.g. stacks, trees, dynamic lists, etc.) and simple algorithms (sorting, merging) as part of the real problem. If you are not doing this already, I strongly recommend a) using a language with built in support for these things, b) using a ready library (e.g. C++ STL, Java and C# standard classes), or c) using your own library (write it once, and preserve it for all problems). Such an approach is adopted not only in this contest; it is a general rule when creating any program or IT solution nowadays.