I got inspired by Disciple's Guide and decided to go a bit nuts. The more I thought about deciding which Tier to pursue, the more I found complexities in the decision. Rather than making a recommendation, this spreadsheet gives a visual overview of how a given drop can impact you. There's a bit of explanation on each page if it is interesting to you.

One interesting thing that I started to track was the likelihood any drop will boost your Light level average up a step. This is important because that simple change can make Tier 1 drops more likely to give you an increase in light. It can get complex and I'm not convinced that algorithms give the best advice. As such, I'm not included that on the page, but I'm certainly open to it if you can suggest a compelling set of thresholds to make that determination.

Anyhow, I'm not actually hardcore about leveling and was more interested in the data.

Check it out.