This "keep shooting that snake & sparky" makes it another yawnfest IMHO.
There are so many games which, if you so wanted, you could break down like this.
MM keep shooting the castle
AcDc keep shooting the ramps
Xmen Keep shooting Wolverine
PotC keep shooting the ship
SM keep shooting Doc Oc
All of these are obvious strategies that anyone walking up to a machine can do and get some enjoyment out of the game without understanding the deeper rules lying within, as well as scoring decently.
There are also games where the more experienced player can exploit a particular strategy
MB keep shooting the creature
MM as above
JY keep shooting for video mode
STNGG keep shooting warps
AcDc keep shooting the bell
What I look for in a game, is that there are numerous different strategies to getting a decent score, and more importantly, that those scores are balanced with a decent risk vs reward.
Metallica has all that, and more, with a great art, light and sound package, with some humour thrown in as well. That's why there are so few second hand machines that come up for sale, and that Stern are still managing to sell so many NIB 3 years after it's release.
Mine will be the last one to leave, but it would take something VERY special to come along for me to even consider it.