a little a few much等词作副词修饰形容词比较级时怎么用?

I'm a little better today (than I was yesterday).
Tom has ten books and I have a few more (books,that is,I may have 13 or 16 books.)
Jack is much more careful than Tom.
Jack runs much more quickly than Tom.
Tom has $ 10.Jack has much more (dollars than Tom.That is,Jack may have 30,50 or more dollars.)