My personal recommendations: Fedora KDE, Nobara or Linux Mint. You can’t go wrong with either one of them.

LMDE or plain Mint. Or just go for Debian.

I’ve been pretty content with Fedora for a while.

+1 for mint. I’ve been using pop, zorin and manjaro, but since I’ve used mint I completely switched to daily driving it on my personal devices and my gaming PC, even going so far that I got it installed on the company laptop 👍

Mint is amazing and frankly if its working for you then I think you’ve found it. I stayed on mint for a long time until I relented to a nagging friend and tried out NIxOS and was amazed. If you have the technical skills and feel confident to push through the inital difficulty its well well worth it.

So whats the good?

1. Reproducibility. Ever been annoyed that someone cant help you because they either dont have the time or just cant reproduce the problem? Its no longer an issue. Dependancy is managed by design so configuration and state is transferable with as little as only two files.
2. Declarative. Best way to decibe this is all the benefits of Arch and zero of the problems. Declare your configuration in a file and then have a life. Ive never saved so much time before with any distro. Imaging installing windows, configuring the OS, installing apps, configuring them only once, ever, never having to do that again. Reinstalls go straight back to the way you like it.
3. Reliable. Ive never had a linux distro so stable. The risk and pain of change is a thing of the past.
4. Largest and most up to date repo. Its simply unmatched.
5. The list goes on to other areas like security, scalability and much more but lets leave it there.

Whats the bad?

1. Difficulty of entry. You need to have basic understanding on writting basic code to some degree as you define your config as a simple text file. I recommend vimjoyer on youtube he has some great simple intro videos that will help here.
2. Using apps not in the repo. You will need to step up your config skills here to install that weird app you want. That is only unless you cant wait. If you have time the community is fantastic, a quick app request on the repo has a great chance of being picked up by some legend and added to the repo officially.
3. The wiki, its no Arch wiki, thankfully you dont really need it. The community maintains a bunch of configs for hardware and apps on the repo which is weirdly not advertised half as much as it should be. Alternatively just search github for configs from other nixians.

A bit late to the party here. These are my two cents based on my own experiences

Mint:

I’m currently running Mint on my work laptop. It’s rock solid, never had any problems. Apt is good, Flatpak and Brew had everything else I needed. I love Cinnamon and I like that minimal tinkering is needed.

Bazzite:

I have a big gaming laptop running Bazzite. I mostly use it to stream games to my shitty small laptop to have a poor-man’s Steam Deck. I am really impressed! Everything was just setup and working out of the box. I like the immutable concept. Everything is running in Flatpak and Brew. I can add Distrobox if anything else is needed. And rpm-ostree if I really need a program running “on the system”. Haven’t bothered tinkering with anything (other than changing wallpaper) because I liked it out of the box. One problem is documentation. There’s just so much documentation written for non-immutable distros which won’t work, since immutable distros works differently.

OpenSUSE Tumbleweed:

I have a small 11" Chromebook with touch screen. ChromeOS was EOL on it, and Tumbleweed and Arch were the only viable option. Went with Tumbleweed just to check it out. I’m not impressed. I hate the package manager, and the settings are all over the place. I don’t really see the appeal and I much prefer EndeavourOS. With that said, it works. So I haven’t bother changing distro. Everyone seems to love it, but I don’t get the hype. Probably a me-problem.

EndeavourOS

It’s baby’s first Arch. It’s just Arch with sane defaults and everything set up for you. I love aur and I love that any program you may think of is just running on Arch. Endless possibilities for tinkering. I loved it, but not currently running it. I do wish I had it on my Chromebook but I haven’t bothered with the jump. I have broken it a couple of times. 100% my fault messing around with stuff I shouldn’t have messed with. But it was never that hard to fix. And the wiki is AMAZING! If you don’t do stupid shit, there won’t be a problem.

Debian

Running it on my home server. Rock solid stuff. Great for running a server that doesn’t require bleeding edge and which is just super solid and extremely well documented.

Manjaro:

Stay the fuck away from that stupid shit distro. It almost bricked my laptop and required tons of work to get back up and running. They do stupid shit and the way they hold back packages is just stupid. I wouldn’t recommend it to anyone. Just go with EndeavourOS or Geruda or something.

Ubuntu

No. Just run Mint

NixOS

Really really cool, but you need a bachelor’s in Linux and a lot of time to really reap the benefits of it. Shit documentation.

What’s your GPU? Nvidia’s you will need to use the proprietary drivers, AMD it depends on how old it is but newer ones should be good with the default driver.

From the issues you mentioned on Ubuntu I think it’s likely you have an Nvidia since it doesn’t play completely nice with Wayland all of the time, which sucks because X11 is halfway out of the window.

Another thing I think you probably know but just in case, you can install different Desktop Environments on the same distro, no need to change distros for that. So you could install Plasma (and yes, Plasma is KDE) or Gnome on your existing mint installation.

Honestly I think Mint is great for beginners and if you’re happy with it there’s no reason to switch. One thing I always recommend though is keeping /home in a separate partition so you can reinstall or switch distros without deleting your data.

I’m tossing in another vote for Fedora. It’s honestly about the closest you’ll get to “Standard Linux”.

It’s one of the most bleeding-edge distros while still being very stable and secure (Rolling Releases are more up-to-date but I’ve had enough issues with them). Traditionally a Gnome-First Distro but the word is that the next release will promote KDE alongside Gnome (That said KDE is already great on it).

Debian’s pretty good, or if you need something a bit newer, OpenSUSE Tumbleweed seems pretty good as well in terms of a beginner’s distro.

I would say Fedora workstation if you hate the idea of getting arch-like distros but Manjaro if you just dislike the daunting procedures to get your arch work

I settled on Manjaro over the past year but since arch isn’t in consideration, I’d vote fedora or a derivative like bazzite due to its additions for gaming.

I ditched Windows for a year ago and have been happy user of Linux Mint since then. It’s solid, nice and easy to use. I don’t like much of customization, all I want is easy to use and solid system and Mint with Cinnamon is all that. Years ago I was distro hopping around but now I don’t need that.

Honestly, Debian 12 bookworm with the KDE package is pretty damn solid. It’s all I need for my desktops.

I use Mint for my main gaming PC, FWIW, totally rock solid