Personally I think a big problem are all these 3 in 1 type modem/router/wifi solutions and the inability to debug which part is causing problems. These devices

Personally I think a big problem are all these 3 in 1 type modem/router/wifi solutions and the inability to debug which part is causing problems. These devices a less expensive but seem to always compromise some functionality. What that is, is rarely evident from the box/review/manual. For a long time now, I've always recommend to people to buy standalone cable/DSL modems and figure out how to get the analog signal strength/error correction/retry counters from them (and return it if you can't get them). Then spend the time replacing connectors in your house and getting the modem as close to the curb as possible. Then pick a good wifi solution, and tweak that until its as clean as possible. Wifi and modem standards evolve at different paces, and its silly to upgrade your modem or router every time you want a newer wifi standard, or for that matter change your wifi to get a newer cable or DSL modem.