mrytp, listen. Listen very closely, because this is important. I actually really liked this level for the first 4 sections (especially the flags) - not quite FFFFFF quality, but close. However, there are a couple things you need to learn.
1) Annoying =/= hard.
2) Hard =/= good.
3) If a level is shit, you can replace it.
I mention this because, holy crap, "Ice" is BAD. The trinkets are shit, the challenge is shit, the graphic style is shit - the whole thing feels like a massive departure from the rest of the level, and I have to ask - why didn't you replace it? Why didn't you just... NOT do it? Clearly you have at least some understanding of good level design, because the rest of this level is superb. Surely you can see how bad this is... right?
i wouldn't care so much but it's a 25 room level and 9 of them are visual-only so -1 room is actually a big deal
I don't really have specific feedback for any other level (all of them are good!), but everything I just said also applies to "Impossible (almost)". That level is also really, really bad.