Fasttrack increases throughput and lowers latency but it isn't noticable unless you are on a wired network, local network or pushing the limits of throughput of your router. The idea of fasttrack is to give priority to specific machine, traffic, packets, ports etc. without slowing its traffic for processing.
fasttrack script (https://wiki.mikrotik.com/wiki/Manual...)
/ip firewall filter
add chain=forward action=fasttrack-connection connection-state=established,related
add chain=forward action=accept connection-state=established,related
using fasttrack it may reduced the cpu load but your simple queue is ineffective, therefore youll need to create additional rules, so you may exclude traffic not to "fasttrack" in a certain machine, packets etc.