I know its only a tester...
The game is good considering it isn't finished and takes me back to my days of playing the first few GTA games, the finished version ought to be better.
Thats if you are releasing a finished version.
However I can suggest some improvements...
-Get rid of the monotone annoying scream from the peds
-Malteasers for fists and blood? come on...
-Better AI
-Some music would be cool
-Better Weapon selection
-A highscore system
-Try and capture some of the more recent GTA's side-missons
Good effort nevertheless