Mine are just really dim. My old Incredible's light was really bright.
+1 to that. I definitely preferred the button lights on my Incredible.
To the OP,
Go to Liquid Settings>>General>>Automatic Backlight then check the "use custom" box. Then click on "edit other levels."
At the top of the screen it shows the light level the sensor is picking up right now. The max is around 10,500 (I got it to read this by shining a bright LED flashlight directly at the light sensor.) In my normal office lighting conditions it reads about 1280, and when I cover it with my hand it goes down to about 160. So it's pretty accurate.
Below there is a list and settings for different ranges of light levels.
The top one is by default (0 - 159). That is the lowest range. If you are in a deep cave that is what light range your phone will be on.
And then at the bottom of this list is the highest range, say you are flying in space and get too close to the sun, you will be on that range.
And of course there are many ranges in between.
You can adjust the lower limit of each range, but I wouldn't if I were you.
What I would adjust is the Screen brightness for each range, and the button brightness for each range. For example I didn't like how dim the screen gets when you are in low light conditions. So I changed the screen level at the bottom range from 21 to 28 just to see how that works. And then you'll notice also that by default the buttons are only lit on the lowest three levels, and they are set for a brightness of 30 at those three levels. (You can set them up to 255 brightness if you want, but they don't get any brighter, so you might as well use 30 as your number. They are either on or off, they don't have different levels of brightness.
So anyway if they aren't coming on when you think they should, maybe go down to the first range that they have a "0" and change it to a "30". If you still aren't happy, go down one more so that the top five light ranges all have the buttons turned on.
Hopefully that helps you.
edit: My mistake. I thought I was in the Liquid Smooth 3.2 ROm section.
If you are running that Rom, this post will be helpful, if not, then it won't.
Sorry.
