If you want to shake things up with an arch derivative you can try EndeavourOS, there are a lot of different DEs you can choose straight from the installer

One of the Fedora spins, or if you are feeling brave Fedora Silverblue or Fedora Kinoite.

If your laptop is on the potato side I would personally avoid kde, it's much lighter now than it used to be but still heavier than other options. Mint looks good in my personal opinion and, again in my opinion, is a better alternative if compared to ubuntu, it's based on it but with some improvements. The default flavor comes with cinnamon, but if your laptop struggles it's also available with xfce, which even older machines should be able to handle.

I'd say give a few Arch-based distros a try, or just straight up Arch if you're feeling adventurous. Arch distros are just slim and speedy, which could be good for your old laptop. The new official archinstall tool makes it relatively easy compared to installing Arch the manual way, but if you're looking for more ease of use EndeavourOS is a great option.

MX Linux.

Imagine Linux Mint Debian edition, but it isn't green and there are a lot of useful GUI tools. It's also so near to actually being Debian that you can just install things meant for Debian on it. It also runs a backported kernel for modern graphics driver and chipset support so you get your stability and your performance all in one.

Glad you found what you were looking for!

Regata OS is a gaming oriented customization of Opensuse Tumbleweed. I’ve been using it for a year without issues.

I think Arch Linux could be for you. You can install it with archinstall script. It's relatively straightforward.

Fedora is a good choice. It is stable while being fairly up to date. The only issue is that (I think) proprietary drivers aren't included by default.

My vote goes to OpenSUSE Tumbleweed. It's a beautiful system, and the most stable rolling release I've ever had the pleasure of running. I've tried so many different distros, and I always end up coming back to OpenSUSE.

Check out Fedora Silverblue.

I really think having a stateless root is the future of computing. Silverblue has a big focus on using Flatpak and containers to cover most use cases.

The only issue is the default Gnome would probably be too heavy for your hardware but (as others have mentioned) you can overlay KDE and use that instead.

Edit: as others have said below check out Kinoite for a Silverblue spin with KDE by default.

I have used Linux for awhile and settled on pop!_OS for my home desktop/laptop use.

I'm personally using Kubuntu because a lot of programs I like are built for Ubuntu already and while I'm fine with messing with building from source for some things, for most, I like my binaries prebuilt on a distro package service. Also I like KDE Plasma.

Stick to the main distros unless you have a specific reason to use a novel one. Despite its drawbacks, KUbuntu is great and I definitely recommend it. Once you find a thing or two you don't like about it, you can swap to a distro that does those things differently and you're off to the races :)

PS Linux can breathe new life into a laptop, but if apps are too intense for your hardware it won't magically give you more RAM.. With the exception of Minecraft Prism Launcher + Fabulously Optimized, then your Linuxtop turns into a NASA supercomputer

KDE is surprisingly lightweight these days. Maybe try the Fedora KDE spin. Or if you need it even more light weight: the LXQt spin is also not bad.

I'm not sure how lightweight Fedora is, but it's currently my favourite distro. The harder choice for me is the desktop environment, I'm currently using KDE, however Gnome looks more modern.

Linux Lite is worth a look, it's designed for old machines as well as folks moving over from Windows.

Edit: Porteus is another good lightweight distro to checkout. It's light enough to run off a USB but can also be installed on the hard disk. It has KDE, Xfce and Cinnamon environment options too.

I'm a Linux vet who's been around the block. I've tried all the major distros, used Gentoo for a few years, Arch the same, and a bunch of smaller distros.

Nowadays, I just want my computer to start up and run my programs with as little fuss as humanly possible. I'm far too lazy to rice or optimize anything, and I have little patience to troubleshoot the next big awesome thing.

Consequently, I use Kubuntu with Wayland. It chugs along and does everything I need it to.

Honestly I don't have a recommendation right now, but if Valve ever gets around to actually releasing SteamOS 3.0 (holo) I'll probably install that.