I know I am always looking for petsites and petsims to play, so I would say it is worthwhile. Just know that making a petsite isn't easy and takes quite a bit of time. I would do some research to see what the current trends in pet games are. I also highly recommend not officially starting anything until you have a rough plan on what you want your game to be.
The Gaming List has a whole host of other petsite creators that you can collaborate with. You can find all kinds of useful guides and advice for being a virtual creator. It can also serve as a place to market your game; I check in on the site everyday to see what's new.

Keep me updated on what you decide to do! I really want to watch you succeed

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