It's been a few hours in the new router (AC1200 TP-Link).
Initial impression is good. The 2.4Ghz channel seems to be more stable. When I say stable, I mean it's holding the signal better than last router. I'm getting full speed when door is open and around 25mbps when door is closed.
Last night in a diagnosis it said that I'm in a heavily crowded area and it strongly suggested me to move towards a more open area for better reception. I've never seen anything like that before in the past dozens of tests. I do get that, being in the corner most position in the corner most room of the house which is literally next to neighbours kitchen in floors above and below, would put me in a less than ideal position.
Regardless, the 5Ghz seems better to me. Even when doors are closed getting a solid signal strength and test result. Tx rates are also high. For the 2.4 band it's high but for 5G band is way higher. And there is something else. I think. If I move laptop to the worst possible position where I've always received the ********* signal, the connection still drops, not as bad as before. But after a while, couple of minutes, it gets better,
way better. As good as it gets. I think beamforming isn't a gimmick if that's what is at play here.
Look at this, the speed in the menu bar and the stats in the dropdown. This is the place for possible the weakest reception at farthest point.
I'm yet to use it a bit more so I can confidently say that my problem is solved. But I'm happy with the result so far.
Thanks to everyone for the suggestions and guides while I was frustrated over this. I'll check the range vs noise when I get time.