Speed games for me always relied on luck manipulation (getting the right npcs, avoiding traps etc.) The only instantaneous teleportation spots I know of are the NS to DS and the Teleport room in the Rouges Guild (I think this is the name of it).If you want a cool speed run look at the video done here. (Hoping I won't get banned for link posting
)
http://speeddemosarchive(DOT)com/MightAndMagic6(DOT)html
IMO speedruns are quite boring. I always loved leveling up and interacting with my party over the course of days or months.
If you want a challenge try some of the peasant games (heck TCC pt2 was extremely challenging for me!)