How about making category where you spawn in point A and must reach point B as fast as possible. It can be done on many maps and include flying from one spot of planet to other (from equator to north/south pole), from planet/moon to other planet/moon and other variations.

Example:

Other category is "Refinery + Assembler" category: build get those 2 machines working as fast as possible.

Also this run is pretty good, the only problem is to determine minimum requiriments of "late game".

Actually for "Any%" speedruns set in "normal" scenarios more suitable tactic is change world setting to easiest possible, then either repeatedly respawn and scrap starter ship, capture cargo ships or build antenna, place pirate name on it and give it to SPRT (https://steamlists.com/space-engineers-sprt-drone-spawning-antenna-names-and-their-drones) to scrap drones (best variant is multiple antennas named "Stash Beacon", what spawn peaceful Stash-Sattelite with 6 minute cooldown). In these 3 strategies you mainly will get resources by scrapping. Also, mining strategy also can be speed up, as these speedrunners didn't played on most optimized settings.

Most of Space Engineers speedruns including category extensions and survival mode (some of them is non-valid or from wrong game, but most is normal): https://www.youtube.com/playlist?list=PLUUWQNnKFbltntbrI27aGyl2tWm9Nvpp5