I don't think this really makes much of a difference. At least for me it didn't. Sometimes I remove cards that are too easy, sometimes I see that the next time

I don't think this really makes much of a difference. At least for me it didn't. Sometimes I remove cards that are too easy, sometimes I see that the next time to review them would be 6 months down the line and I leave it in, because the cost of leaving it is so small. What has made a difference though is thinking about wether I still actually want to remember the contents of a card. Sometimes a card comes up that I haven't seen in months and I think "you know what, I haven't thought about this at all outside of Anki and I don't think that'll change." and then I just remove it. Sometimes I create a nearly identical card again later on, sometimes I really didn't need to know something.