TL;DR: How to choose the width of the confidence intervals one reports?

I am working on a paper on statistical technological forecasting.

Our model produces confidence intervals for the date when a particular milestone will be achieved. I am now thinking about how to report the results.

One line of reasoning is that you want the results to be as informative as you can, so we would report 90% confidence intervals.

Another one is that you dont want to overstate your results, specially on a domain such as the one I am working on where model error could be as high as 1/3 of the models. So your confidence interval should be commesurate with the expected base rate of model error (eg 70% confidence intervals in this case).

I think I am not framing this problem correctly, so any thoughts would be appreciated.