Hopefully I am not conflating concepts in a corrupt way. I am still new to this concept of sense data. I am aware of my misuse here.
Just a stray thought: We have failed to take into account the processes that happen below the conscious states - namely those that go on in the brain. Many neural networks are activated in relation to any given sense datum and some do not appear to bring into perception any given thing - we perceive the main event each time but many smaller events have taken place further strengthening future sense datum ready for activation - reminding us of some thing at a time.
I propose more than one sense datum at a time - those that fall into conscious and those which do not. I further propose that there is nothing meaningless going on in the brain - that we are misunderstanding what meaning is and therefore discounting meaning happening that is not perceived.
The brain is its own universe. We are the actor.
My studies show that a thought need not be in the conscious. A thought comes with its own machinery.