Yep. Even half-charged buster often is more effective against some of them. My biggest issue is that some enemies take no effect from the lvl 3 beam when caught in its path. The grasshoppers are a larger version from the og MMX, so I'm used to one-shotting them.
I prefer Hunter as my casual difficuly, but will do Veteran for the challenge. Can't get past Sigma first form though. If I can Hadouken both dogs then maybe, but even then, it still takes 2+ Hadoukens on Sigma. Actually did a Veteran run and quit there after one game over to Sigma.