tl;dr: Is there a supported router that is (possibly) newer/has broader range than the Archer C7, but that is not as expensive as an "enthusiast" router/AP? Is the D-Link DIR-878 any good?
I currently have an ISP provided router + WiFi AP with an connection of 240Mbps. Since the house I live in has very thick walls, I get almost no signal from where the ISP AP is to the places where, say, my wife is working or some of our TVs are. (That's in the 2.4GHz range; no hope of any signal in the 5GHz range).
I pulled a (long) ethernet cable and took an old TP-Link TL-WR740N and installed Gargoyle (a derived firmware from OpenWrt) and it is serving the parts of the home that are not served by the ISP gear, but its throughput is both low (especially with a small armel NAS where I have Debian installed), since its ports are 100Mbps and, more importantly, its range is also moderately small (but still better than what the ISP provides). The problem here are also the very thick walls of my home.
I spent many, many hours on the OpenWrt site and this forum reading and rereading hardware recommendations, looking what I find in my country (Brazil) and something that is supported by OpenWrt and I saw that the Archer C7 is quite probably a safe bet regarding support and affordability.
I can get the Archer C7 for about R$650 which is about US$100. Since I am a little bit worried about the range of reach of the routers, I wanted to know if there is something that is has broader range than the C7, but is not as expensive as the "enthusiast" router/APs (some are upwards of R$3500 which would be something about US$500).
Is the D-Link DIR-878 well supported by OpenWrt? It is only a little bit more expensive than the Archer C7 and it supposedly supports "MU-MIMO Wave 2" which is something to be said to improve reception/range...
If that's not a good option, what should I prefer? Any comments are welcome.
Thanks for any help.