Add more LAN Ports

Adding a Gigabit Ethernet switch will do the trick. Be sure to buy good quality Ethernet cables. Using CAT 6 Ethernet cables would be best. Sure CAT 5e should work but a good quality cable should be used. Cheap Ethernet cables sometimes have RJ45 connectors that are not to the IEEE specifications and the contacts are of poor quality. It is not just the connectors the RJ45 body can be off a bit and lead to the improper seating of the connections or be sticky in the port on the switch. 

Spend enough for a solid solution and don't buy a bunch of weak links. If you get a Gigabit Ethernet switch that does not seem to work properly just send it back and get another brand. If you want to see how well it works when you get it use a large file and run a transfer test between two local clients. There are software solutions you can use to run performance tests to know what you have. 

In the end though if it works well for you and you like it that is what is important.