I already did that and I'm quite happy with the performance at the moment. Kwin really rocks but I'm hesitant to become friends with the plasma concept in KDE. Ranting from my gut on news.yc is not really productive but I really think it's just bad design. It gets in my way and on my nerves. I don't remember such feelings from Unity or Windows.

Qt5/QML2/Wayland are all great ideas but these can't compensate for bad design. If I install a fresh KDE it feels like a Desktop to show your 16 year old friend and explain them the concepts but actually never do more than playing around with the knobs. This is of course nice and legit but it's not a Desktop for getting work done.

So maybe I just want a switch to disable activities and widgets and get some more RAM and calm for that.

This is really difficult and I don't want to ridicule any effort and the hard work that went into KDE. I'm not involved and don't have a lot of better ideas to offer. So don't take me too serious - I just have the feeling that a lot of these efforts will perish due to bad design and strange ideas about UI.

The switch for disabling activities and widgets exists; you can enable it by not using activities and widgets. It's not like they're forced upon you.

If you feel that strongly about widgets, you can switch to the Folder plasma view, which is a standard OSX, Windows XP-style desktop without any extravagance. Or just widgets on the standard desktop, if even folders aren't austere enough for you.

(I agree with you about activities— so far as I can tell, they're basically virtual desktops without the convenience; ironically, the only 'advantage' they seem to have is having different sets of widgets. But they're basically unintrusive— I certainly don't remember the last time I interacted with them on my desktop)

I don't feel strongly about widgets - I just did not like how KDE does them. I can rotate them.. cool. They have some funky mouseover-menu..cool. What about the functionality? Ah... well. It's not there. But as I've wrote.. I was not able to get some reliable hardware widget that displays the information gkrellm provides. It was cumbersome to adjust the seperate network/cpu/disk widgets on the desktop and the information was rather useless and barely readable. I hate to say it but this stuff worked with SuperKaramba on 3.5...(http://netdragon.sourceforge.net/ssensors.html) and well I don't know why I care soo much about it.. it just feels backwards having to fight with all this stuff while remembering how well it - at least from a user perspective - once worked.

Disabling the Desktop in a folder is the first I'm doing when on a new system with KDE. I can see how it is useful to have multiple folders accessible on your desktop but I can also do it with the traditional Desktop and widgets. Never felt the need for it - but there are a lot of different use-cases.

Activities are a great idea in theory. But the implementation got stuck halfway before being really useful. I would love to have a usable version of that and lot of use cases for them e.g. monitoring and terminal stuff in one activity / IDE in another and another one for the browser/mail stuff.. but it never felt right and I was not able to pull that off. It also seems like the programs in each activity do just stay in memory and not really separated... so it's some good idea that is probably really difficult to get right.. okay. No problem with that, but the thing that annoys me a little bit is that they feel so forced upon me. If I don't want to use them they should be to able to configure away completely - remember - I can even rotate my widgets.. ;) as they are unrelated to virtual desktops in KDE (at least that was my conclusion after spending time with them) and only annoy me...

I could go on.. and basically these small little things are what I would say is bad design.. however I can see how difficult these things are and how diverse the opinions are on these debates. But I have the impression that nobody is really happy and as long as there is little improvement in these areas I'm not really excited about QML and mobile stuff..

I still think that the majority of KDE users are running Linux on older machines for doing programming and office work and well... nobody seems to really care about this anymore. Unity suffers from similar problems.