Converted TM router not fast enough

I've flashed my T-mobile ac1900 to Asus RT-AC68U with latest firmware. I have 1GB Internet, after the upgrade I am getting hardly 60-80 Mbps on LAN. Earlier on LAN with ac1900 I used to get 870 Mbps. Flashed it again to Merlin, currently running Merlin v384.19 still getting same speed, no change. When flashing I picked the latest CFE 2.0.0.6 US AiMesh, will that be a issue?

Screenshots from my settings:



Appreciate if...

Converted TM router not fast enough