Don't take things too literally
mcogilvie's comments are both wise and correct, so there is very little I can add to that particular aspect of the problem, but perhaps I can add something else. I have also had that same problem, after I moved from paper to computer in the late 90's and have been trying since then to find a computer app and a system that really give me the support I want.
First of all I would like to add that GTD is a general framework of thought, and adaptations to your own needs may not only be necessary, they are even encouraged by David Allen if you really need them. And I would also like to add that I think you could benefit greatly by getting a better task app, but more about that later.
In response to your first question I would say, as you even say yourself, that you obviously cannot just put one single action on the Next list(s) and then wait for a whole week, so you simply have to solve it. How you solve it is up to you. What I might have done, if I were using paper or a basic list app like Google Tasks, is either:
1a) move a week's worth or two of tasks onto your Next list(s), and perhaps put a mark on the ones that really are Next right now to distinguish them from the rest, or:
1b) work straight off the project's own task list. This will work particularly well if all the tasks all require the same context, but will work anyway.
1c) get a better app that can distinguish between true Next and subsequent (intended) Next. Those apps also handle contexts for you. Omnifocus (Mac only) is probably the best (but I have never tried it), MLO is powerful but perhaps a bit unwieldy. I use Nirvana, a mid-level-app that allows me to handle this situation, but Zendone, another mid-level app, is more flexible when it comes to this.
As for your second question, I confess that I too have no use at all for a gigantic list of micro-projects - 800, no way! If you want to build a complete hierarchy with full dependencies etc you probably need MLO or Omnifocus, but what I do (with a 2˝-level app) is I use the highest level (called project) for my major 30 k objectives (real-world "projects", usually with a 3-30 month horizon) and for my 20 k AoRs, and I use the task level (called actions) both for true Next actions and for subsequent Next actions AND for subsequent sub-projects and projects at all levels, with individual tasks or hints etc in the task notes, i.e. I manually convert these projects-in-disguise to individual tasks when they are "near". So far I have not found the perfect app that has the overall simplicity of use and the power to let me do what I want.
Just as mcogilvie indicates, I too generally keep project support material (budget, purpose, people, whatever ...) totally outside of the task app, but what I do want to keep inside it is the general outline of the "Do" steps, i.e. tasks, sub-projects etc all the way up to AoR or 30 k level.
EDIT / Clarification about major objectives and the "Do" outline:
To avoid any unnecessary confusion, when I mentioned major objectives at 30 k and keeping the "Do" outline in my app, I am (of course?) referring to all this from my own personal point of view. For example, one of my AoRs is "Consultant" (for hire). A typical client job in this area is just a regular project that goes under that particular AoR, and my project covers only my own direct participation and associated activities, regardless of the fact that what I do for the client is probably just a small part of a much larger "project" or effort in their eyes. I do not attempt to keep their entire "Do" outline in my app, only my own "interface" activities with them and my own individual activities for delivering the agreed result and achieving a good overall result for both them and me. If the client has provided me with a time plan for their total effort, that is just reference material as far as I am concerned, and regardless of how large their effort is, it is normally still just a regular client project, not a 30 k major objective, for me. (I don't know if this clarification was necessary, but better safe than sorry.)
Last edited by Folke; 10-19-2013 at 02:29 PM.