We've only recently started using Tomcat (6.x) as our Java servlet container for various production web applications. We're not using particularly advanced functionality, and generally Tomcat config for each app is extremely simple. It seems to me that installing multiple Tomcat instances (which I understand is extra easy to do as a Windows service with Tomcat 7) would not much increase maintenance effort, while allowing each of our apps to be completely isolated from the others, and e.g. not be affected by a service restart following a server config change designed to help only one of the apps. High performance is not crucial in the case.
Is it as simple as that, or are there good reasons why one might want to share instances between several apps? Bonus question: is there an obvious way I'm missing to re-read server config without bouncing the Tomcat service?