Having a set schedule for work and leisure time each day (e.g. work between 8am to 6pm then leisure) and then adjusting weekly/monthly based on your mental health seem to help with the issue of constantly obsessing over what you could do more. Then you are allowed to enjoy your leisure fully without any guilt, because you know you'll review things in the future if it's too much. It's similar to the idea of having a set time where you think about your life problems to avoid ruminating constantly. 

You might wanna review the idea of neglectedness to asses impact. The idea isn't necessarily that climate change is less important than other causes. Just that there are already a ton of resources being put into work on climate change so adding more resources there will have less impact.

This article addresses neglectedness among other things.

https://forum.effectivealtruism.org/s/x3KXkiAQ6NH8WLbkW/p/ER4gAtS5LAx2T3Y98