Take what you will from this. You might say that the bailiff should not be ignored, after all they know the water as well as anyone. On the flip side, doing what others suggest takes away from what really matters which is figuring the place out. I have to say that not using a rig because it's in vouge is completely illogical. By all means try to be different, but if you're going to avoid using a rig at least have a good reason for it.
This makes it even more important to find them.
Chopping and changing isn't likely get you anywhere until you understand what your problem is. There are a million things you could change but it could take months to find the right one. Your best piece of tackle is your eyes. You need to be changing what you do based on what you observe, not just a whim or a hunch. You've not mentioned on this thread if you've been on feeding fish on your sessions. That's the first thing that matters.
You have a half decent starting point in that you know what doesn't work i.e. what you've been doing. To be honest, based on what you've said so far, I strongly suggest that finding a few spots is all you need to do. A good spot can turn a difficult lake into an easy one so you just need to know where they are.