First time I see a roach I will probably be hitting it with my crowbar, most likely destroying some furniture in the process, as they dont live around my area. As for other insects, as long as they dont trespass in my living space, they are fine. Spiders are welcome since they help to control other insect issues, until they try to make a home behind my monitor or pc.
As for insects spreading disease: not that many actually do, and it will mostly be the ones who act as parasites: mosquitoes, biting flies, fleas, and a few others. Ants might but there are plenty other reasons to keep them out of your house beyond just that. Either way, if you keep your home clean, the bugs will look elsewhere to settle.