One thing I wish they would do is let the computer drop them out of warp. Sulu does it manually!
A millionth of a second off would make them crash in to Titan or wherever they're flying to.
TOS is full of that. In the episode where they went back in time and had to beam the 20th century people back into their bodies and they were moving back in time rapidly Kirk manually gave the order to beam them back. Then Scotty or whoever did it delayed a couple of seconds (for dramatic effect). That could have been a couple of hours difference the way they were accelerating through time. It really needed exact timing there. There's no way the computer wouldn't have to plot that out. Still its not as cool getting the computer to do it.