I fully admit it. The stories that me and Caitlyn are writing, in total, has a HUGE cast! By the end, we must have like 30-40 something characters (although I'm probably off mark on this. I haven't been able to find the cast list file which bugs me)! Some of them are ones we already know, like Grovyle, Wigglytuff, Chatot, Darkrai, Rayquaza and such. Others are completely original characters, like Slowking, Lilly, Dean, Aisling, Woody and others. The 5th story arguably has the largest cast (it is a big world after all!) overall (and this is including major and minor characters).
Is there a limit you set when it comes to characters for you? At the end of the 4th story (the last chapter of it taking place at the end of the "timeline", with possible foreshadowing to the 5th one), we want to write a big epilogue that reveals the fates of all the characters we've written. Some have gotten married/are dating (Mike and Patrica, Randy and Lilly, Carl and Audrey, Deanna and Chip), some have gotten nice jobs (Ratso and Orochi are part of a spy organization, Jon eventually takes over Randys radio show when he retires), some have returned home where they belong (Harold is reunited with Herman, Woody goes back to the Pokemon World to Hoenn and becomes a professor, Timmy heads back to Guardia and lives with Sophia) and so on and so forth.
Some characters, such as the Marowak from Marowak Dojo, are actually given names and personalities. The Marowak? His name is Eldrian (take out the 'r' and switch the letters around and you get Daniel, which is his little brothers name), the older brother of identical twin Marowaks, and he runs the Dojo his grandpa left him. His little brother Danny? He is the Guildmaster of a certain spooky place that we've come to love to fear- now called Nightmare Town in this universe, it was once known as Lavender Town, the Noble Purple Town from R/B/Y/FR/LG. Nightmare Town, like Lavender, is- as described an Jack the Umbreon "full of lost spirits and hauntings" - but don't think it's all that bad. The ghosts there are nice and friendly (although they do like to prank you at times), and the town always has two events every year: their big fun Halloween party (which is almost always hosted by Danny and Jack), and their honoring the day the old Pokemon Tower was attacked (known as the "Rocket Massacre" to them) with the Marowak Festival (think the Summer Festival from the anime, except with dozens of Marowaks instead of one maiden) to pay their repects to the dead. Every year at the festival, seeing as there are always a few who haven't heard of it yet, Danny the Marowak recounts that horrible day when Team Rocket invaded... Daniel and Eldrian were just two of the orphaned Cubones after that day, but their parents still haunt the town, not wanting to pass on until they know for sure that both of their sons are safe.