Soap spray is the usual recommendation given for "organic" insecticide. Organic is a relative term of course, but it will generally breakdown quicker than most other insecticides.
Hot pepper (I assume this is a capsaicin spray or powder?) is not going to work with insects (or birds), but should be effective against mammals. Wild pepper plants evolved their high capsaicin content to discourage mammals from eating their fruit. However it was okay for birds to eat the fruit as they did a better job of moving the seed (and I think the seeds are more likely to survive the bird's digestive system - but I could be mis-remembering that).
Are there specific insects that are posing a problem? You could try to encourage natural predators for these insects (ie. larger insectivorous insects, and birds). I've seen things like veg being grown in tropical conditions (Costa Rica) and I don't recall insects being a problem. However, there were so many insects, birds, and bats that were would be plenty of insectivores to keep them in check. Of course with such bio-diversity, it also means you really want to be very restrained when using the more deadly insecticides and herbicides!