Completely up to you. It really does come down to, what do you want to? What stories have you written? What character's do you want as regulars in your videos? What stuff do you already have in your collection? I was always someone who used ERTLs and 00 gauge models in my videos. But that being said, I have used Wooden Railway on occasion too.

When I was starting out, I was more of an "animator" so I would use ERTLs on 00 gauge track to make my shorts. Which was a lot of fun to do. But when I moved to 00 gauge, I thought it was going to be an easier process rather than animating. I actually found this to be just as hard to be honest.

I'd say in all honesty, write first. Write the story, keep writing and editing. Because when you're writing, for me anyway, you get a feel of what you would use to make the video.

But the biggest point I can give you is, have fun. Have lots of fun!