My current config: https://pastebin.com/TkFcUwar
I've read through the entire tlp.conf, looking up things I'm not sure about, I think I have everything optimized for max battery life but I'm no expert. I got a decent boost already, but is there anything that I'm missing that can be improved? Also are there any tips or tricks I should know about?
It's an ASUS K53E, i3 2310m using the iGPU, Centrino Wireless-N 1030(works perfect OOTB), and an SSD running Fedora. The CPU stuff has to stay commented out since it doesn't play nice with this laptop.

For example: remove everything you do not need (services, fancy screensaver, background processes ....)

There is a system called ACPI that controlled that stuff until systemd and everyone writing a WM added their 'power manager'. You can find or make & configure useful stuff there but it takes reading. With today's laptops, apart from changing from black/white to 'grey on grey' powering off cores, hibernating instead of suspending, hibernating if you pause to break wind, slowing the cpu 50%, there's not a lot you can do. I use mine as a desktop.

Might also be some bios settings to slow down timings maybe disable hardware not needed.

I'd think backlight is the biggest user of power. ?? dunno maybe

What is the health of your battery? Most laptop batteries don't last longer than about 3 to 4 years, even when optimally used. And the ASUS K53E is a 9 year old laptop model. If you have battery problems and the current maximum capacity is less than 80% than the designed capacity, I would not hesitate and replace it. This is because I don't think the readings are accurate when the max capacity drops significantly.

A quick search on Ebay found me a plethora of replacement batteries for about 20 USD. I can really recommend doing so as it is one of the best and one of the cheapest upgrades you can buy for your ageing laptop.