When I prepare research statements, I use a systematic logic called the "three W's", namely: What, How, and Why
The "What" describes your research problem (research statement)
The "How" described your proposed research approach.
The "Why" describes why your proposed research matters. That is to say, why it is important to the stakeholders, the business case, anticipated benefits, etc.
Just try to use this logic and you'll have an excellent research statement.