Yeah, I still love to use the some PM tools just for myself. Thats ok I think as long as it helps you do your job better.
** There is a sneaky way of going full Product Manager on some issues. That is using whatever you created as a marketing tool.
At my company Bliss we created a Trello Product Roadmap SPECIFICALLY because it could be shared publicly. I wouldn’t have gotten the buy-in unless it was a public facing feature and marketing tool.
If you blog/tweet/post about the product and how it’s being managed then it’s a win all the way around and a great use of your time.