Is there a trick in logic to get regions to distribute on the grid every X seconds. So if I have 40 sound effects and I want to line them up so they each start on multiples of 10 seconds... ?
I would suggest setting the grid to show time instead of measures. You can also set the tempo to 60 bpm so that it aligns with seconds, and maybe change the time signature to 10/4, or whatever amount of seconds you may want in another circumstance. By changing the time signature you can customize the grid so that it will fit the regularity of your samples, allowing the snap to grid feature to be useful as well as giving you a visual.
From there I would set each region to the desired length (10 seconds) and either use the loop feature or copy/paste the regions as needed.
This approach could be problematic if you have a specific tempo or time signature that the rest of the project relies on. In such a scenario you could set up these sound effects in a separate project, convert to new audio files and import them to the other project. This would set the samples at the specific length and the loop or copy/paste approach would also work in this setting.