大一点 is “bigger than”（e.g.网球比乒乓球大一点。Tennis ball is bigger than ping-pong ball） 有点大 is “a little big”

Dearsunnysayo , The difference between "大一点" and " 一点大": "大一点" can be thought of as an adj phrase and can be used in a sentence below: "A 比 B 大一点." "A 的確是大ㄧ点." "一点大" is also an adj. phrase, and usually is used in a negative sense. Ex. "A祇有一点大." About "安定有点儿大": Maybe this expression exists, but I personally have never heard of it. I hope I have made my explanations clear. The difference between "大一点" and " 一点大": "大一点" can be thought of as an adj phrase and can be used in a sentence below: "A 比 B 大一点." "A 的確是大ㄧ点." "一点大" is also an adj. phrase, and usually is used in a negative sense. Ex. "A祇有一点大." About "安定有点儿大": Maybe this expression exists, but I personally have never heard of it. I hope I have made my explanations clear.