Hey, @niallon11.
STEEM Monsters is taking off, judging by how many posts there are about it in my feed every day, so hopefully that means there will be time to figure this all out and maybe catch it when prices are up (whatever up is). As for playing—I could see myself doing it, but as you say, most of my time is already spent on STEEM, trying to gain some rewards. We'll see. Might need to go back through some posts and see if there's any clues as to what makes what more value. So, far, my guess is, common cards are worth the least, while rare, epic and legendary are worth more. :)
i'm having look at it there for the past hour just trying get to grips with the whole site. I can see where the attraction is and where the possibilities are too. If the game gets big with big prizes people will spend a lot to build a solid team of monsters. I'm not sure if i want to get involved but i do like where they are going with it.
I've not looked at it to that great of depth, but from the bits and pieces I've been reading from posts and comments, it sounds like there's all kinds of things they could do with it. I do have to say that I am amazed at the level of the graphics and what animation there is. There will have to be more to it at some point, though, for it to continue to grow.
Personally, I'd like to see it go into mobile AR, like Pokemon Go. You could just go down the street, or even around your house, battling individual monsters. I guess it's turned based role playing now, but still, I think it takes on all kinds of looks if they had the time and resources to expand it out.