You can adjust the trackpad/pointer settings via the GUI in Chrome OS, but I have found that the mouse speed still needs fine tuning.
Open a terminal window by pressing Ctrl+Alt+T. At the crosh shell you can type the following command to see the usage of xset:
xset m ?
The following output will be shown:
usage: xset-mini option ...
To set mouse acceleration and threshold:
m \[acc\_mult\[/acc\_div\] \[thr\]\] m default
To turn auto-repeat off or on:
-r \[keycode\] r off
r \[keycode\] r on
r rate \[delay \[rate\]\]
After playing with different settings, I have found the following command produces the most optimal feel and acceleration:
xset m 0 0