Welcome adventurer. The current RPG in this Community is Ruler of Kings II which is a custom text based RPG and while similar to Dungeons & Dragons it is an independent and self-regulating role-playing system. I dare say, for the purpose of solo online entertainment while still maintaining a detailed character and imaginative development you will find that ROK II is far more diverse and engaging as a text RPG. You may also read: Ruler of Kings II vs Dungeons & Dragons.
That sounds like my exact situation. I'm new here too, I've done some other Play by Post systems before to make up for my lack of being able to play with a group. I plan on playing Hero Kids with my kids when they are ready but in the meantime Play by Post is fun. I found this site when searching for other systems and it looks interesting, I'm still learning it.