My suggestion is to have speedrunning categories for adventures. (These would be listed on speedrun.com as ROM hacks for Spore, just like Mario ROM hacks and custom maps for Minecraft.)

Sure, you have the in-game leaderboards, but those don't have any videos so you can't see how the times were achieved, and for all I know they might not even be legitimate.

Main rules for adventures:

1. The adventure must be accessed using Quick Play. (Accessing the adventure from the Space Stage means that you cannot see who created the adventure, making it hard to verify that the user is playing the actual adventure and not an easier version of it.)
2. The video must show the user selecting the adventure from the Sporepedia. (This is also to verify that the user is playing the original adventure.)

Some adventures would have their own categories and rules. For example, Bahaha 500 Time Trials would have two categories, Any% and No Shortcuts. (In No Shortcuts, you must stick to the main path to get to the end.)

Thank you for your very well articulated suggestions and enthusiasm! I am not too familiar with ROM hacks but I will definitely look into it. These are very good ideas, but there are not very many people playing Spore at this time. From my expirience gathering runs for the Stages, people are not very interested in resubmitting their videos here. It has been slow going and a struggle to get the submissions in the existing categories. I am worried that the adventures will not be very competitive. However, I would love to be proven wrong. Also, I have been trying to keep the leader board very clean, I personally do not like miscellaneous categories or categories with very few runs (I have removed over 30 miscellaneous and empty categories since becoming mod a few months ago). But if there were more active members I would be happy to add them back. Perhaps if either of us find record videos either on youtube/twitch we could keep a running list in the forums.

There is a Galactic Adventures page on speedrun.com now! Check out https://www.speedrun.com/Spore_Galactic_Adventures for all the best Galactic Adventures speed runs!