Why don't you handle all your traffic through the Netgear and bin the TP-Link?
all devices -> Netgear -> HomeHub
In effect you'll be using the hub as a modem basically. The way the anti-bufferbloat algo works is that it's called 'fair queue / controlled delay' or fq_codel. I don't know what the sliders do, because the whole beauty and point of fq_codel is that it's zero-config: it just needs to bandwidth benchmarking.
At the moment, once you download something massive on your non-game devices, the Netgear can't do anything about bufferbloat for your game devices, because the fq_codel isn't operating on them. In effect you've got a tollgate on your game devices and an open highway on your other devices, so your pings will be increasing as if you only had the HomeHub. If it also handles the non-game devices then it's going to be far more effective for you.
Another thing that's happening is you're double-NATing. This shouldn't normally increase latency, but it's a router hop, and a router hop means CPU usage (within the router). Never underestimate the crapness of an ISP-supplied router. If you want, you can bin the Home Hub too by getting a DSL modem like a Draytek Vigor 130 connected between the Netgear and your phone jack.
Edited by zzing123 (Fri 04-May-18 21:19:21)