I always like the idea of creating something that persists in the world when you're gone and the idea of slowly building up your "web". I like the idea of "Survival and domination" - especially if there was a mechanic that meant you could be "dominated" by other players but still be able to progress - for example, an "allying" system in which better players gain from you by protecting you and you give to them as you progress.
However, I struggle to visualise how this game would keep people coming back. That is, once you've mastered the basics of "Web building", what else is left? You get bigger and make bigger webs? Don't get me wrong, I think that your idea could work really well in a game, but as a game itself - maybe not.
However, if you are planning it to be a starting point for a game which you will then expand. I love the idea of being able to be different insects - termites, ants, bees! There is a lot of room for imagination in this setting.