When I first saw this gem many years ago I figured that the ray gun disintegrated soft tissue and material like clothing- apparently the aliens could fly around the universe but hadn't developed a blaster strong enough for bone. Maybe their enemies back home were jellyfish-like creatures in suits.

Yeah, Plan 9 gets a lot of digs yet there's plenty out there that are far worse - killer shrews and the one with a monster consisting college kids under a carpet comes to mind.
In trying to make the aliens sound different, I noticed they didn't contract their pronunciation. "I won't" becomes "I will not", etc.
Teenagers? I kept waiting to see a bunch of astro-punkers and see 30-year-olds in Captain Video uniforms. OK, I'll tough it out and keep watching. In the shoot-out, the cops are skeletonized - but where are the clothes they were wearing? OK, I'll tough it out and keep watching.
And the lobster that screamed like an elephant? That was the last straw. I fast-forwarded until the end.
Most of the actors didn't appear anywehere else - I can see why. However, Dawn Bender was nice to look at. For some reason, I like Harvey Dunn - his acting didn't seemed strained. The old cars were neat too - a trip down memory lane for this old fud.

"Teenagers From Outer Space" makes "Plan 9 From Outer Space" look like "Citizen Kane"!

There is another scene where the police are having a shot out with the bad alien. The bad alien hits one of the officers with his skeletonizer gun which reduces him to bones. The other officer reaches over and puts his hand on the neck bone to check for signs of life. Not too surprisingly he doesn't find any. Oh, and I almost forgot; the monster from Red Lobster.
Just remember: I was as good as any and better than most-Vincent Freeman in Gattaca