Same issue. My main perspective in OF is to show all available tasks, so my list can get large. I wanted a way to narrow the view to just the things I wanted to do 'today', but I still wanted to view OF at times to see the bigger picture, when I needed to. So I used a small app that lived on the menu bar which let me list things for today (like you, I did this at the start of each day, figuring out what I could/wanted to do).
I had also been following the GTD mantra, but my problem with it was always that no matter where I was, I could usually do any of the tasks. With today's cell phones and mobile devices/laptops and the nature of my work, I never really needed to define contexts such as "work"/"home" or "phone", etc. What I finally did was abandon pure GTD and use contexts differently.
My three main contexts are "immediate", "ongoing", and "next task". (I have others like "Waiting" and "Omnifocus" that are not primary contexts.) "immediate" is the context that lists those tasks that I want to do today (these are the tasks that I used to copy into the other app I used to view today's agenda). So each day, I make those tasks that I have time for "immediate". For other tasks that should be done "now", they are in "next task". When my immediate list gets small, I scan the "next task" for items that I have desire and time for today/tomorrow and move them to "immediate". Some tasks are long term but I only focus on them once in a while; they are "ongoing" and generally stay that way. (When most "immediate" tasks are dealt with and/or if I have a little time I'd rather spend on that long term project, then I do a little work on it. But it stays "ongoing".)
I use start dates for most tasks, but if there's an available task that I don't want to tackle today or for a few days, I don't want to update the start date, since I may find I can do it today and if the start date were changed to the future, I may not find it. That's my reason for using "immediate" and "next task" instead of twiddling with start dates.
The bottom line is that my contexts let me decide which to do now and which to hold off a bit, instead of letting OF decide which are next and available. I rarely have sequential projects any more (since stepping down as chair of my department, I have little admin work to do!) so my situation works well with this OF workflow. My main perspective lists the contexts and I focus on "immediate" tasks. But I also have a quick way to expand the other contexts, like "next task" when I have to. So I no longer need to use a second app to list my day's activities. I know that I can use flags in place of "immediate", but that would require me to switch between several perspectives.
And, yes, I add things like pay bill and buy lightbulbs to a Single Actions project (I have a lot of single action projects these days).