If you look at the ultimate example of the savior, how much agency did he have, knowing his foreordained path (you shy away from the term mostly predetermined)? From a worldly perspective, his life was as bleak as it gets.
Our agency is absolutely affected by our level of knowledge of our divine nature and god’s plan. Joseph smith had agency and considered using the plates initially for causes that countered god’s will. Was it possible? No. The lone time he was allowed to use his agency contrary to God's will was with Rigdon, he paid an excruciating price.
We do believe the meek and miserable inherit the earth, right? Or should we just go for a life of materialism because He is a merciful God who digs agency?