you could enhance the original pac man when you add some kinds of power ups: * 1 time you could walk through the wall * or teleport * etc.
Or upgrading your character: e.g. spending 1000 collected coins into running faster. Or Health. So you could be hit by a ghost, 2-3 times until you are dead.
Starting the game with almost highest speed of fire rate doesnt give me the good feeling of upgrading. Sry, I really want to feel that I have to work on improving my next skill level.
A real goal would be really useful. Maybe every 10 level a boss. There you can get a special item an loot. If you pass level 50 you can unlock survival mode...