Some great post here - a shame it's been so quiet of late.
Our house is relatively new, and when we viewed it, I was sold as soon as I saw it was wired with Cat5
The patch panel is located in a big cupboard on the landing. The switch that came with the house was only 100Mbps, so that was upgraded pretty switfly to a Netgear GS724Tv4. I wanted a NAS, and since there was a wall-mounted cabinet, a Synology RS815 seemed a good choice - that's now full with 4x 3TB WD Reds. The server also resides in the cupboard, a XEON E3 with 32GB, currently running Server 2012 primarily as a Hyper-V host, with 5 VMs performing different roles - domain controller, mail server, media server, WSUS server and certificate/ADFS/management server. The router is also in the cupboard, a BiPAC 8900AX2400 connected to the ONT for the FTTP internet connection. The FTTP install was really neat, since we had a spare Cat5 socket right next to where the fibre enters the house (village has overhead cables!) so we avoided a massive run of fibre around the outside of the house. All the kit in the cupboard is protected by a UPS.
Elsewhere we have a couple of desktops and a couple of Surface Pro 6s for regular work & gaming, three Squeezeboxes of various flavours for music, and the PS4 and Samsung TV mostly all on wired connections (apart from the laptops) leaving the Wifi network relatively uncongested.
Next project is a server upgrade...