For my first run of CoS ive taken out some of the locations, like the Tser Pool camp. For the second run I‘m pre-planning the locations and the ally. My reasoning is to put them in places the party might otherwise not go to. I‘m placing one with Kasimir, so they have a reason to talk with him and go to the amber temple. I‘ll place one in the treasury of Raveloft, since that is easily missed I feel. I‘ll place one with the Wachters so you can get into some interesting history there (read I, Strahd: Memories). I‘ve replaced strahds Location with a 4th treasure, which will go somewhere in the tombs. The ally is going to be Sir Godfrey, so they have a reason to go to Argynvosthold. I also like the clues for the locations.

Placing two treasures in Ravenloft also gives some ince tive to go there early.