Any opinions on whether or not this game should be parent-clone with the NWS version? (same goes for Fire)
I think there's too many differences. Not only are they 2 different releases (like eg. Climber crystal screen and NWS), but unlike the Crystal vs NWS games, these are reprogrammed.
Note that there are no strict MAME rules regarding parent-clone sets, I usually pick what makes the most sense. Sometimes I'm just lazy and do whatever.
In this case and especially Fire, the ROM and LCD graphical portions differ so I think it's a no-brainer to keep them separate.
I've always felt that Egg should not be listed as a clone despite having the same ROM. Besides the LCD's partially differing, they were released and marketed as different games by the same company. Same with DK Circus and Mickey Mouse where the graphics will entirely differ. I certainly see why people will disagree here, so I don't feel as strongly about it.
Definite clones: Helmet (v1), Judge (Green), Balloon Fight NWS, Climber NWS and Super Mario NWS.