A little late to the party but welcome back!
Even in the short time I've been here its evident you're the heart of many threads, so I'm glad everything has worked out.

I had a similar situation to me once in Uni, you can often go into the router settings and block any users outside of your comp and devices, and run a guest WiFi for the mates when needed.
Also, I don't know if this has been already said but if there are a lot of different WiFi signals in your area or you see quick dips in connection during peak hours, but if so, it might be a good idea to change the WiFi channel to something less popular - there are a few guides online if you need this.