And for the record, my own workstation is running 10Gbe as are several editing workstations over CAT5e. The server is about 90ft of cable away. This is not supposed to work, but it has for the last two yrs or so with zero issues. We’re running Netgear 10Gbe switches and Intel cards. The CAT5e should be fine.
I do run a 10GBe NAS at the home site, however it’s using CAT5e as well. This is the blog series I wrote, in case you feel the need to equip your home with 10Gbe 
https://www.smallnetbuilder.com/tags/Cinevate
If you are running some high wall CAT outlets, just match them to power outlets within a few feet as mentioned previous.
if you are planning to have a few WIFI access points, try to keep them separate from your Smartthings Hub. If you plan on using HUE (highly recomended) keep in mind that the bridge too will require an Ethernet port…as would a Lutron bridge if you’re planning any Caseta bits.
Smartthings as a security system has some major flaws…no one who knows the system well would recommend it over something like DSC. Sensors that drop with low batteries and zero warnings, or motion sensors that require resetting frequently are a few of the obvious flaws…although the newly added device health (if you turn it on) will help with you these issues. Cloud based hubs like ST really “violate” certain security system basics. ST is a nice complement, but certainly not a reliable replacement (yet) for more established vendors with respect to security.