@BoredSysAdmin
Could you please elaborate a bit on this detail, any technical reasoning (i.e. why is this better)?
set channel width to smallest 20Mhz - yes - this option will reduce max performance, but will likely to significantly improve wifi strength and stability, which in result will make wifi work better.
I'm assuming that this is just a setting field on the Tomato Firmware?
All of your other advice etc, I am aware of and have done. My guidance was provided by my bro-in-law that is an IT guy. All of his advice lined up exactly with yours, except he never made any mention on the channel width.
So, you have me very curious on that one.