Anyone think Valve might make the editor easier to mod?
Editor mods like BEE2 are great, but they have limitations. The main limitation is that you can't put more than 32 different icons on the object palette. There's no scroll bar, as it wasn't designed with extension in mind. In addition, there's no way to add custom menu items to objects. For objects with multiple varieties, the only option is to use the menu from something else, such as a button. Therefore something like a logic gate might say "Button type: Weighted, Cube, Sphere", even though it's something completely different. Another thing I've noticed is that some objects that are similar to others (like the fizzler-like objects) don't have the same editing controls as the object it's based on, but that might just be the fault of the mod. (no offense!)
Considering which developer we're dealing with here, I sincerely doubt these limitations are intentional. I'm sure someone at Valve has seen the mods people have made for the editor, and I wouldn't consider it out of the question for them to make some changes to improve its moddability. What does everyone else thing? How likely does this seem?
The "fizzler-like" issue you're referring to is more general: certain item classes are hardcoded so they can't be used for custom objects. So there's no way to make a truly fizzler-like item without modifying the existing one.
But I don't think this will be changed, VALVe isn't working on Portal 2 anymore.
This is the best editor mod. You can download it through steam. Thank me later.
PortalStories.com
"Oh, in case you got covered in that repulsion gel, here's some advice the lab boys gave me: DO NOT get covered in the repulsion gel."
Valve doesn't really want anyone to mod the editor which is why they gave us basic items. Besides, the best maps are made with hammer and I'm not arguing with anyone about that. (Yes PTI has some good puzzles, but because it's easy to use, people aren't trying too much and you need to dig the workshop to find the best PTI maps).
I find it hard to believe that Valve wouldn't want people to modify the editor.
BTW, I tried a bit to find where the list of items on the palette was stored in memory using Cheat Engine (so the values can be changed without restarting Portal 2) but no luck. If anyone else can figure that out (or better yet, a way to force it to reload editoritems.txt) it would be possible to hack in a scrolling system controlled by keyboard shortcuts or an overlay window.
If that's your thought, Valve should have some explenations for us.
The choice for the editor items has been carefully made. For example; there are no doors because it would made it hard to see what would be the exit and what would be a random other door.
Introducing new elements to the workshop also means introducing new limitations to the custom elements. If you really can't make good puzzles with the limited tool set of the pti you might want to think some more; there's still a lot of good puzzles coming out.
And yes, hammer is always the better option if you want to mod custom stuff 
No. Valve had a plan with the editor, and these mods whilst very good are outside of the scope of their initial plan, which was to offer a quick and easy WYSIWYG editor for people with no technical knowledge of hammer to make basic puzzles.
With the mods, I've seen some people think themselves as "professionals".
Hey, so I've actually asked the guys who created the PTI, about these limitations. While they did not intend to limit what modders could do with it. They just wanted to make a PTI that worked well for the average user. They figured, if people want to mod the PTI themselves, that's fine (and cool!) but they were not going to go out of their way to make features on an editor that is only supposed to be used for proofing simple puzzle ideas.
There was no reason for them to spend weeks implementing features that would allow modders to make the PTI more like a real level designer, when the already have a (sortof) robust one out there already. If you want to use the PTI, go ahead, have fun with some of the mods, but if you want to get into real level design, use hammer, and never touch the PTI again.
Also, if I didn't mention, Valve isn't going to be adding more modding support to the PTI... I asked them about this about 18 months ago til about 12 months ago if they could add features, but the same vibe came back every-time.