I disagree with Super User and the stock theme. They look too much like Meta Stack Exchange (and can thus lead to off-topic questions from users who follow links here).

@JoeFriend - Is it possible to retain both classical as well as new designs themes , for those like me who likes the current theme by providing an option to display site in old theme as well as new. By default the new will be visible.

@SwiftPushkar No, that isn't possible. The entire effort is focused on reducing the support costs around theming. If we have a new and an old theme, then we are increasing our support costs!

@JoeFriend - Oh ,In that case it looks like this is not possible. Anyway we will adopt to the new one soon.Thanks :-)

Well, it could have been worse.

I left my voice as a downvote. I don't much like the new site designs. This is my truncated rant.

I'm not sure what to do with the LHS menu: it takes up considerable space without really seeming to be useful.

What is the "Cadillac treatment" an overpriced, oversized, lumbering yank tank unsuitable for any real work?

I remember the good ol days when it was just @Jin doing all the site designs across all the SE sites. Those were the days...

Oh we're improving things by making everything look the same, undermining and undoing individual branding! Oh...good? Why does Stack Exchange/Stack Overflow (the company) never seem to consider asking questions in those sites dedicated to giving sensible answers to redesigns of their own sites? Will you please start anticipating dissatisfaction and - prophylactically - ask in Graphic Design and User Experience about these redesigns and 'improvements'.

clicks tongue what a shame. Everyone's losing everything. . .

Incidentally, in case it wasn't already clear, I hate everything about this and don't really see the need given the lack of explanation as to the necessity; the possibilities offered by CSS-theming with custom CSS properties (CSS variables) seems to inherently undermine the 'cost' argument.

You've noted that Canonical's top bar has been removed from Ask Ubuntu. This Ask Ubuntu Meta question states "Canonical reached out [...] about making some design changes on Ask Ubuntu to reflect the official Ubuntu site's new design guidelines"; the wording suggests that SEI is legally obligated to implement this top bar under the Ubuntu trademark license agreement. Are you sure this change doesn't violate SEI's agreement with Canonical?

Wow, those designs are pretty lame compared to the old ones.

What happened to the custom votebutton shapes? Those need to be added back in, stat.

So...can I just ask why this is even necessary? The cool designs are already there; it probably took more work to take out the cool stuff than just leave it as is (speaking in my professional non-developer opinion =) Also, those designs really ... made a site special. Cutting them out is a bigger loss for a lot of people than I think it's really worth.

@JoeFriend "The entire effort is focused on reducing the support costs around theming. If we have a new and an old theme, then we are increasing our support costs! " I wish this would be made as one of the big stand out points of all this change; if this were just a stylistic change, I am fully against it as it is unnecessary and really doesn't improve much of anything. It looks like change for change's sake. But with your clarification as it is a necessary change that will lower the support costs, I can really get behind it.

@JoeFriend +1 One can always use a browser extension to adjust the default theme to their liking. I agree with their decision to reduce cost around theming. Most of the users use just one variant of Stackexchange and the new users honestly do not care. Its the content and community that is important. And let's be honest, at the current expansion rate of Stackexchange you will run out of colors very quickly, not that it is a bad thing ;)

-1 This was clearly designed without any community feedback. In addition to the horrifying implementation of the sidebar (which I see still hasn't improved itself to appear to have less whitespace as has been repeatedly pointed out), the lack of the custom votebuttons is just cruel. They were delivered in the same exact resource as the custom badges, so it would be a downright lie to claim that dropping them makes maintenance easier. Shame on you, Stack Exchange.

@forest I think that your comment is an exaggeration. I don't see how a bit of white space and lack of custom buttons and other trivial things alike prevent anyone from posting quality content on the site.

@Bright I'm not sure why you need to bring a strawman argument into this. Re-reading my comment, I cannot see any place where I discussed anything other than aesthetics. You are implying that I claimed that the poor visual appeal prevents posting quality content which is, of course, ridiculous. I get that you like the changes, and I have no problem with that. I just find it rude to take it to a personal level by putting words in my mouth with a strawman.

Not good enough.

I can hardly notice the differences between various sites. All beta sites look alike now. It kind of looks like change for change's sake.

Not sure why you need to make a simple thing so complicated. Just define standard sprite dimensions, and let each site define their theme meeting those standards. That's just one time effort and then you can forget about it. You say you want to cut costs, but you go ahead and increase your costs by reinventing the wheel.

Make the themes (colors) customizable individually by users - problem solved. By these changes you're only breaking things like this. I'm not a web developer, but I'm fairly sure such thing must be trivial.

I keep seeing comments all over the place saying "The left navigation is horrible" and "The left nav uses too much whitespace". Hint: Go to your profile & settings page and then to preferences - there's a gorgeous "Hide left navigation" checkbox that works wonders.

@forest The tone of your comment is that of a hysteric outcry. Now you are trying to fall back on the argument that you were just doing geometry and coloring. Other than the hysteric tone of your comment, the argument is otherwise just utterly trivial. Moreover, it is hypocritical to accuse me of wrongly using strawman while you're doing that yourself, re-reconsider "so it ... Stack Exchange".

@JoeFriend "If we have a new and an old theme, then we are increasing our support costs!" There's an easy fix to this, don't waste time making new themes. Anyway, since your development team consists of world-class developers (and managers) and spend plenty of time on Stack Overflow, User Experience, and Graphic Design, it should be easy to make your code reusable with any theme, without having to rewrite code for each theme. All you have to do is define a site-specific sprite, and the code should work seamlessly with it.

@Sean It was stated ages ago, that with the implementation of new designs there will be no more custom vote buttons.

@forest Maybe you missed the whole point of this question (or didn't read it?) because Joe specifically said "Please review the mockups and feel free to provide constructive feedback in answers below.". You know, another way of saying that is "give us feedback, community", the one thing you are complaining about. Time to pull your head out of the sand :-)

Instead of adding functionality your changing themes; it's nice to see that you've solved all other issues and freature requests :-|