On those specs? Well, you could try Librewolf and ungoogled-chromium, but I imagine they'll be a tad sluggish.
NetSurf, Dillo, and Links2 are more suited to low-power machines, but they don't support HTML5. Also, NetSurf's JavaScript implementation is fairly old, and the other two don't support JS at all. Furthermore, Links2 doesn't support CSS (by design).
Well, yes; after all, I have been able to modify even proprietary software to fit my own preferences; but it's clear (and also explicitly stated) that it's supposed to be used mostly as-it-comes.
I can't say I've tried Niri or PaperWM before, but if they're based on GNOME then maybe I'm being a little harsh.
Slackware, Gentoo, the Mandriva family (OpenMandriva, Mageia, PCLinuxOS, ROSA, ALT Linux), Void, Alpine, Chimera, Venom, CRUX, Exherbo, Paldo, the PiSi family (PiSi Linux, old versions of Pardus), and Solus (eopkg is a fork of PiSi).
On those specs? Well, you could try Librewolf and ungoogled-chromium, but I imagine they'll be a tad sluggish.
NetSurf, Dillo, and Links2 are more suited to low-power machines, but they don't support HTML5. Also, NetSurf's JavaScript implementation is fairly old, and the other two don't support JS at all. Furthermore, Links2 doesn't support CSS (by design).