Youtube encourages you to make longer than 10 minute videos since they can sell more ad content and unfortunately, that a long time to keep someone's attention. Unless you are doing a step by step how to, I would try to keep the videos between 5 and 10 minutes long. Personally, I rather a long video be broken up into sections so I can easily jump to the part I want to see next or go back easily. As far as content, I enjoy product reviews, product comparisons, and how to's followed by train running sessions. I know small kids LOVE just running the trains with little or no talking needed as the action speaks for itself.
I have also subscribed to your channel and look forward to your new videos!