I own my own cable modem.
The UNIX philosophy was always to save simple, focused tools that do one thing and do them well. The OP seems to agree with this - and I do as well - with my network setup. Though, at this point, routers, switches, wireless access points, and cable modems are all really software applications running on an ARM or MIPS processor or something like that. I've had great experiences using aftermarket OSes such as OpenWRT.
It kinds of reminds me of the 90s, when one could get an all in one TV, VCR, and DVD player. Those things were awful!
I was very lucky to have Gigabit cable pulled through my house's attic during a recent round of house work. Highly recommended. Punch down tools are cheap, and much cheaper than paying someone else to do it.