I think dogecoin has won the battle for supremacy in the Character Coins department. We have others like pepecoin or mona coin.
At first I believed Mona was going to the moon, but that was not the case. The problem with these character coins is the community and support behind them.
If you have a lot of people supporting it, and the popularity never wavers, then you're looking at a solid character coin.
If you want to invest in character coins, perhaps the best is to:
look at the community behind it. How many?
How enthusiastic are they?
I also think the cost has something to do with it. You can get dogecoin for dead cheap compared to something like Mona, and that's also what makes it really appealing.