Not much I could recommend TBH. I’m a slight Dell fanboy, however, I don’t like their XPS, nor their Inspiron lineup. All I will buy from them is Latitudes. Maybe check out the Latitude 5400 / 5410 (14") or 5500 / 5510 (15.6")? They also have some 52xx and 53xx models which are 12" and 13" respectively, and sometimes those feature a touchscreen if you’re into that.
The Latitude lineup is split into 3/4 categories: 3000 series is low-end, cuts out stuff like windows hello cameras and fingerprint readers. 5000 series is the mid-range and in the past it was a little thicker than the 7000/9000 series, but nowadays it’s pretty much the same. The 7000/9000 series is pretty much the same, just marketed the “premium” of their business laptops, but I wouldn’t buy them. And I believe those also have higher screen resolutions, which you really don’t need, they just eat the battery for not much gain.
Bonus points for latitudes is that, being business laptops, they are made to be upgradable (m.2 SSD, sometimes it has space for a 2.5" ssd if you remove the M.2 completely and upgradable RAM).
I don’t think latitudes have aluminum chassis (but do XPS do? all XPSes I’ve seen IRL were plastic), I think they’re plastic, but they feel pretty nice to me, compared to things like HP Pavilions or Dell Inspirons or Lenovo Yogas and Ideapads. I especially enjoyed the 5x90 series and newer (that is 5x00 and 5x10 now) touchpad, which is a rare thing for me to enjoy on laptops (I’m very picky about touchpads) and I like the models that come with trackpoints.
Probably not something you would enjoy, if you want aluminum stuff.
I think the M1 will go head-to-head with a 6-core mobile i5, but don’t quote me on that. In day to day activities, you probably won’t feel a difference. But I hate macOS with a passion. And IMO I don’t think a jump from Ivy Bridge to anything newer will feel much snapier, unless you have a lot of open programs. Have you watched your CPU load? Do you really need a CPU upgrade?
A chassis upgrade is probably worth it, because I know how much better is to move from a run-of-the-mill laptop to an ultrabook (at first I didn’t believe, until I tried it), but a CPU upgrade is questionable, especially if you run Linux. I had a Dell Latitude 5580 (a slightly thicc boy with an i7 7th gen and 16gb of RAM), then “downgraded” to a Toshiba Kira (5th gen i5, 8GB of non-replaceable RAM) and didn’t feel a difference in performance, but the weight, oh my lord, soooo good. Then I downgraded again, because reasons, and I’ve ran a Dell E5440 (4th gen i5, 16gb of RAM and Fedora KDE Spin) and it was perfectly fine, but then again, I don’t know what you use it for (I just had like 50 Firefox tabs open, around 5 chromium tabs open, a terminal, latte-dock and remmina, later moved to sway, so even lower resource usage, but KDE was perfectly fine).
Personally, again, I wouldn’t spend that much money on a newer laptop, but now, my tastes slightly changed and I’d rather get an aluminum-built PineBook Pro or build my own with a NexDock 2 Touch and a SBC (either my current Pi 4 or maybe a Ryzen 1st gen SBC, like the DFI GHF51), but I’m going insane.