7 Sins of Map Design.
Tests that require crouch jumping for the solution.
Musical website Moddb
I hate "custom visuals" maps that don't have any hammer skill in them.
That includes re-uploaded pti maps, stylechanger stuff etc.
... Yes, it's custom visuals but it doesn't show any hammer skills, and it makes proper hammer maps harder to find.
And of course people who refuse to learn and keep making the same mistakes over and over again, even though you point that out to them. So annoying 
That one I can excuse because it's not the users' fault. It's part of the Workshop.
Blue Portals required much of this, along with the side flinging concept. But you need to remember, it was made in a different time period when only ninjas pretty much played Portal. Crouching while flinging does not do as much in Portal 2 as it did in the original Portal, same goes for side flinging.
I really don't care for maps that the puzzles are based on where the portals are placed, rather then the portals themselves. For example, a puzzle that is 100% based on lasers.
The more you give, the less appreciated it will be received.
I pretty much understood Blue Portals when the mod came out, I wasn't a ninja at portal, I was a noob.
Portal Dreams Mod... It's going to be refreshing, Like lemonade... Mmmm don't make me thirsty,Blue Portals was made between 2008 - 2010. The whole majority for types of players switched when Portal 2 was announced in March 2010. That's why the first half is all hard flings, quick timing, and much like Logic Portals while the other half was all about elements and such.
If I had a good enough reason, I would do things differently.
The more you give, the less appreciated it will be received.
Blue Portals somewhat has a similar design to logic portals. (Glass stairs and warm textures and magnets...)
It was greatly inspired by it. But I'm glad it now stands separate rather then a complete clone. 
The more you give, the less appreciated it will be received.
It was my 1# favourite mod, got any news on Refresh?
Portal Dreams Mod... It's going to be refreshing, Like lemonade... Mmmm don't make me thirsty,