My bag of tricks for hiding tasks but not forgetting them includes the following. This assumes that I'm usually looking at Available taks rather than Remaining tasks:
- Start Dates: Whenever possible, use start dates rather than due dates. For example, if on Tuesday you realize that the grass is going to be getting really high by the end of two weeks, but there's no chance that you'll mow the lawn during the week, you give the Mow The Lawn task a Start Date of Saturday, and a Due Date of the Sunday eight days later. Then that task doesn't annoy you during the rest of the current week; it's invisible. Of course, if you don't get it done by this Sunday evening, you won't do it before the coming Saturday, so you might need to update the Start Date again.
- Perspectives: Or, you might realize that mowing the lawn is _always_ a "weekend at home" task, and so you create a "weekend at home" context. You create a "work" perspective that excludes it and other home tasks, and a "weekday home" perspective that excludes it and all work tasks, and it only shows on the "weekend home" perspective that you also create. Home tasks that you could do on a weekday or a weekend just have a "home" context and they're on both Home perspectives.
And that "weekend home" perspective excludes things like the "weekday calls" context, for calls to your insurance agent and other people who aren't going to be manning the phones on the weekend. That "weekday calls" context does, however, show in your "weekday lunchtime" and "days off" perspectives. Whee!
No, you don't have to have this many perspectives; my view is that when you have too many tasks staring you in the face, you find a way to make the not-relevant-now ones go away, and sometimes that way is a perspective.
- Project Support Materials: Maybe it's not just Mow the Lawn, but also Mow the Lawn, Trim the Roses, Spread Grass Seed If Appropriate, Spread Fertiilzer If Appropriate, and Check For Mulch Against The Siding. You might combine all of these into a Lawn Maintenance Checklist that you store outside the system, so that you have only one task ("Complete Lawn Maintenance Checklist") in your list instead of five.
If the "if appropriate" bothers you because it involves remembering and that's not mind-like-waterish, you could have a dated log, plus a description of the rules ("spread grass seed every quarter") tacked inside the garden shed door that notes when you last did a task on the checklist and when it should be done again.
If you don't want to store the checklist and the dated log outside the system, you could do as I do and have a "lists" folder where all of the items are On Hold and you create various lists and reference facts; they're project support materials, rather than actual parts of the action/project/context system, but it's handy to have them in Omnifocus so that they accompany that system to my phone and iPad.
- And of course there's Someday/Maybe. If you've reset something's Start Date repeatedly, that suggests that that thing is Someday/Maybe, rather than an active project. When something is made Someday/Maybe, it can be useful to take its details out of the system. For example, if you planned a vegetable garden and made a bunch of actions involving seeds and seed vendors and when to plant, and then you realize, no, that's not happening this year, you could either delete that stuff or export it out of your system and replace it with a single "Consider starting vegetable garden" item in your Someday/Maybe section.
- Returning to Due Dates, if a task pops up and you say, "Eh, I'll do that tomorrow" and adjust the Due Date, and that fact has no consequences, then I'd say that the task wasn't really "due". You've been interrupted unnecessarily, and you're becoming blind to things that might really truly be "due". If you use all sorts of tricks to keep your task lists small enough to see everything, then you can just use Start Dates to make things pop up in those lists, and feel confident that you'll notice them. And when something is truly due ("Ack! If I don't mow the lawn this weekend I'm going to have to hire the guy with the tractor!") you'll notice.
No doubt there's more, but that's what comes to mind now.