Different people have different tolerances for long lists. My tolerance is extremely low. So some of my strategies follow. These are all going to be personal examples, just because those are easier than work examples:
- If I'm not going to work on a project this month, it goes in Someday/Maybe and I don't want to see it or even a hint about it on a day to day basis.
- In fact, I may move that project all the way out and into an "idea document". So instead of having fifteen sewing projects in my current project, or two current and thirteen in Someday/Maybe, I'll likely have two current and thirteen, or thirty, or a hundred, in a "sewing ideas" document. Those ideas ore just scribbles--I don't bother with organizing them as projects, giving them Next Actions, anything like that.
- I don't bother to review the "sewing ideas" document on any regular basis, because there are no significant consequences to letting it get stale. If I want another sewing project, I go look at it.
- On the other hand, I DO look at my "gardening ideas" document once in a while, because gardening is time-sensitive--if I don't do that particular project this spring, I can't do it until next spring. But all the same, that review is represented by ONE repeating item in my everyday lists ("Review gardening ideas", repeating once a month.) instead of the dozens and dozens of lines that I would have if all the projects were in the regular lists.
- Some active things also get restructured so that they are one line in my everyday "scan for something to do" lists, a line that points to a list somewhere else. So instead of "Call customer 1", "Call customer 2", "Call customer 3", you could make a spreadsheet of customers that you want to keep in touch with, with the date of the last call. And you could have a daily repeating item, say, "Make five customer calls from spreadsheet."
I don't know if any of that is relevant. It is also possible that you've just overbooked yourself, and that the infinite lists are reflecting a genuine problem, not just a problem in organizing the representation of your work.