Vaibhav has a question:
"I wonder if there is any way to practice improving reflexes against a fast bowler's release?"
There are many ways to improve your reflexes, but not many of them will make a difference against a fast bowler.
That's because the reason you are slow to pick up line and length is not the result of slow reflexes.
Of course, if you are slow on the reflex department, you have some work to do. But ask yourself if you really do have a slowness to react or not, because even great batters against 150kph bowler's have unexceptional reaction speeds.
What the top guys really have is exception ability to read the ball and the bowler. You can read more about the science of batting here.
How to do develop this ability?
I know that sounds a bit too simple, but it really isn't. You need to build up your database of experience, and the only way to do that is to face a lot of bowling.
Of course there are other little tricks you can use until you get enough net and match time. Click here for the tips. But the bottom line is straightforward.
Get in the nets.
Sometimes the most complex questions have a simple answer. This is one of those times!