Well, Bruce Campbell was the absolute best person to cast in this, especially given the dialogue. It makes for a fun, tongue-in-cheek, entertaining film that you can watch from start to finish...

... no matter how bad it is...

... and it could have been better if it made different decisions.

It is supposed to be campy, and it succeeds in being campy... but it shows the grasshoppers too soon and it shows too much of them. Dominant alien invading race or not... they should have done the intelligent low budget thing and kept the critters in the shadows as much as possible.

If they did that it would have been more serious... for a campy Sci-Fi film. That's ultimately the difference between decent z-grade and horrible z-grade, knowing when to hide the critters and knowing when to reveal it.

But it's still campy fun, even if the director made poor decisions.