I know that there's been at least one thread about ladders that I could find, but I figured I'd reiterate it here. As most people know, ladders\ropes\climbing things can be a pain as you don't stick to them, and you can use them to perform ridiculous jumps such as this one:
I would figure that you would be able to modify the func_ladder entity, or create a new entity specifically for sticking to what you're climbing so you have the option. I've compiled the Source 2013 code myself and so I know it's possible to do. I don't know about Source 2007, but the entity code should be translatable if you need something to build from until you move to Source 2013.
Either way I'm pretty sure that there's a some kind of func_ladder cpp file that can be modified.
Second thing is odd clipping, specifically in island. You can do some odd jumps such as the one in the pit under the bridge in the Pirate\Knight area, which many people already know and would hate to see it go
But there's also others such as this one:
Which can get you up to here:
You can use this to jump onto the tree there which could be useful for an SS or an archer, but should probably nonetheless be fixed. The same jump can also be done in the archway of the opposite end of this tunnel.
These clipping issues shouldn't be hard to fix. The ladders shouldn't be that big of a deal either. If anybody else knows of some odd clipping in this or other maps, it would probably be a good a idea for these to be contained in a thread to be able to keep track of in the hopes that they would be fixed.
This is kind of a combination of a suggestion\bug report, so I wasn't sure whether to put this here or under bugs and support.