Welcome to Steemit. I would say whatever you decide you want to write about, do it. As it is, a lot of us end up writing about all kinds of things when we first get our feet wet, which includes Steemit itself. So bring whatever you feel you want to bring.
I've had a Wordpress blog on and off for years, so knowing more PHP would actually be helpful, if that's what you decided to do.
Enjoy!
Thanks for the encouragement! I've had some PHP stuff in draft forever, maybe this will finally get me around to actually finishing it.