I did try Bob's and Angel's, but I found the formulas so nonsensical that it broke the "immersion" for me.
I think I'd be more interested in a mod that added something that fits the game world and just... extended it a little. E.g.: adding aluminium and titanium, not 50 new raw materials that inter-convert into each other in absurd ways -- loops even in some mods!
E.g.: One thing that feels "not fleshed out enough" in the vanilla game to me is the infrastructure related to nuclear power. The centrifuges have no use other than nuclear enrichment and related processes. The heat pipes can only be meaningfully used with nuclear reactors. Etc... Similarly, you never need to use circuit networks, the back-pressure from the belts alone is sufficient to achieve the desired throughput.
It does tweak nuclear a little, giving you a way to use reprocessing side projects for fusion power near the later part of the tech tree.
In terms of circuits, the one area in which I always use them is to control oil refining so I didn't end up capping on heavy/light oil but also didn't turn it all into petrol and leave myself without the resources to make lubricant or rocket fuel.
Space Exploration pretty much forces you to use circuits too in controllijy what goes to your space stations/other planets but it's a long mod with most of the content basically starting after a full vanilla playthrough
On the other hand, I think things like keybindings and mods that fix problems are probably ok (personally).
Factorio: Bob's mods, Angel's mods
Minecraft: Literally every tech mod, most magic
Skyrim: Requiem
Fallout 4: Horizon
That should give you a feel for what the vanilla game is like, and what you like and don't like about it, so you'll be in much better shape to make your own decisions as to which mods look interesting or useful to you.
Then I'd experiment with mods to find out which one you like or not. Some of the most popular mods are probably not too bad to start with (as long as they're not full game overhaul mods or ones that add a ton of content, as those will almost certainly be completely overwhelming for a newbie.. they can be overwhelming even for advanced players).
Also, I'd start with just a single mod or two, and learn how to use those before adding more. It's easy to go mod-crazy, but that's useless unless you actually know how to use them. So learn a mod or two at a time, and then get a couple more.
There are usually videos on at least the most useful and popular mods out there, so those should be of great help in learning how to use them... but nothing beats trying them yourself.
For me personally, the top three absolutely essential mods are Fill4Me, Squeak Through, and Todo List. Don't expect to be blown away by these mods.. they're very small and very simple utility mods.
These days I actually play with hundreds of mods, so the three above won't even give you a small taste of what's possible.. they just cure a couple of annoyances, and add a tiny bit of useful functionality that I personally can't live without. But sooo muuch more is possible!