I take it that it isn't an option to leave your modem or router where it is and run Ethernet into the centre if the house instead, to an access point? You would be keeping your dsl signal healthier that way, but not an issue if the signal is very strong and the cable run very interference-free. Or split into a modem plus a router, and leave the modem where it is, close to the master socket? You've probably ruled that out as running Ethernet cable is too much of a pain? Or else could use a wireless Lan link to another access point in the centre of the house.
I have a modem and a (wireful-only) router very very near to the master socket (modem to wallsocket is 0.25m = obsessed) and run a long Ethernet cable to a WAP in the centre of the house now, for much improved wireless.
It's just that if you can run CW1308, then you could possibly run ethernet. Cat6 can be awkward to run as you have to be so extremely careful with the bends, it's sooo stiff and you'll knacker it if you try too hard. I use the 'minimum radius of a CD' as a general guide. I am running cat7 all over the place now in case I can ever get a cheap 10G switch going (for internal LAN traffic, obviously).