Looking at Netdisco I have 12 VLANs. ISP1, ISP2 (from Dad's house across the valley), OSPF backbone, DMZ, LAN, Guest, Cameras, Servers, Japan, Kids, Management and Test. Everything passes thru PF and only exposes services as required. The Guest VLAN, for example, has no way to get to the rest of the VLANs. Camera VLAN can only talk to the DVR software, etc.
The important thing with securing my public IPs (as with securing anything) is to understand the surface area and minimize risks. With the number of services I'm exposing, I have to be careful. First thing is to keep all OSs up to date. OpenBSD every 6 months and Debian on an ongoing basis.
Next, whenever possible use single-purpose proxies that have been well audited. In my case OpenSMTPD, Unbound and NSD protect the always popular mail and dns servers from attack.
Keeping complicated things off the internet is important. Big CMS packages are constantly under attack. I only run either static pages on my webserver, or very carefully audited custom PHP pages (written with an attacker's eye to exploit injection)
When I expose something more complicated like Guacamole or Citadel that might end up with a known hole in the login screen, I put it behind both SSL and an HTTP simple auth login prompt. It's ancient, and so well tested that it is unlikely to end up with an exploit against it. Or at least less likely than the app its protecting. I've actually been toying around with doing 2 factor auth on these services with a dynamically generated simple auth sent via SMS bridge or IFTTT...
On my internal network, I have my family running linux wherever possible, and keep Java and Flash off the windows PCs. Everyone runs with a nonprivledged account and the OS/software packages/PDF readers are all kept up to date. I think the wife and kid's PCs are probably the most likely things to be compromised on the network, so I keep a close eye on them.
I also take the reactive approach of log alerting, change monitoring and general diligence to the state of my network. If you know what has changed in the last 24 hours it tends to be a small enough dataset to eyeball, and will tend to tip you off when things are wonky. I also have enough logging and data sources (syslog, configs diffs, apache logs, nfsen data, mrtg data) that it would be exceptionally difficult for an attacker to wipe out all trace of their presence.
I do not know of a successful attack against my network, tho I'm not naive enough to think that it hasn't happened. I just haven't realized it if it has.
Its a great hobby if you like this stuff!