You already said sohai contractor put router in front.

All you need to do now move the router to the middle

When you say cable, what type of cable? In front the cable is hidden? Can use optical cable run along the ceiling to BTU.

Something about mesh to consider:

From fiber optic it goes into modem (as most people called it), then to WiFi router where it has 2, 4 or even 8 antennas. I guess you setup the modem and the router are located next to each other.

The WiFi signal at the other end is weak, so you get low speed. If you put another router with mesh capability here at weak signal location and connect the routers wirelessly, the the speed will not get faster even though the second router has strong signal. The maximum speed would be link speed between the two routers. If you have cable connection between the two routers, the speed would be the speed you get at the modem. So, the closer you move the second router to the first router, the speed will get faster and faster.

You mentioned that to pull long cable to the second router it looks messy. My suggestion is to pull the cable up to ceiling at modem, run along the ceiling and go down to the middle of the house and place the router there. My earlier suggestion was to get an extension fiber optic cable, connect to the existing fiber optic cable and run it along the ceiling like I mentioned before but this time put both the modem and router together in the middle of the house. The optic cable is very small and hardly visible