[SudoAlex]

Chances are the worst link in the chain is your ISP provided modem/router. It's the typical device which will buffer several hundreds of milliseconds of data, and it's the slowest upstream. Most sane ISPs won't do this with routers on their network which serve multiple people - it's a fault if they're over capacity (unless they intentionally want it, eg. ISPs vs Netflix).

If you've got little or no control over the device your ISP sends you - there are ways around it. Either turn off WiFi (or don't connect to it), connect a single OpenWrt or CeroWrt router to that over ethernet and get all devices to connect to that router instead. You'll probably need to fiddle around with it to avoid double NAT (eg. setup the OpenWrt router in the DMZ of your ISP router if you can).

Personally I've stuck with OpenWrt - it works just fine. Install qos-scripts and luci-app-qos, set your bandwidth limits in Network > QoS in the web interface, and tune anything else you want. It should enable fq_codel for you.