So on the one hand, good job writers for making me annoyed that he had such an unjust death, but on the other hand C'MON COULD HE NOT HAVE GONE OUT DOING SOMETHING LESS DUMB.
I saw it as just the opposite. He didn't go out doing something dumb, but doing one of the few logical things the characters have ever done.
Tripp's a modern day Howling Commando; he's a soldier at heart, and he's old school. The "if it needs done, get it done," type. The crystals were *apparently* hurting someone he cared about (plus Raina), therefore, the crystals had to go.
Someone elsewhere pointed out that his "pointless" death may be more than in service to Skye's story. We just haven't seen it, yet.
***Blah Blah Speculative SPOILER WARNING Blah Blah***
If the MCU is still bent on connecting the movies to the show and other outlets, then Tripp's death is likely the first step toward the Terrigen bomb. I hadn't thought of it that way, but it makes sense.
Tripp was in the chamber when the mist activated, which served to show that the mists themselves aren't harmful to humans in their natural capacity (unlike the version that Mack ran into, which was a defensive weapon). Even when Tripp destroyed the crystals, it wasn't the crystals that killed him - it was the Diviner. That's what threw shards into his chest and activated the stone skin protocol.
Best guess is that Skye and Raina are the proof that the other Inhumans need to know they're not alone on the planet. Enter Reader, the eyeless wonder from the end of the episode.
There are now a couple of choices. Either Reader and his bunch will realize they can set off a terrigen bomb in the atmosphere without committing global genocide - in order to find more lost "children" like Skye and Raina. OR, someone else (*cough* Ward and 33 *cough*) will set one off in order to fulfill Dr. Nazi's big picture plan, as 33 only wanted to make him proud of her like a good disciple.
The third choice would be for Cal to set off a bomb like that in hopes that it would make the world safer and easier for his daughter, so she won't be the only one like herself in existence.
I think the Agent 33 version is most plausible, given her background, and if Ward thinks what he's doing will in any way help Skye, then it feeds his delusion that he's still on her side.
A terrigen bomb would also fuel a couple of seasons' worth of storylines, while also setting up the film in 2018. Someone's going to have to come clean up the metahuman mess, so who better than the royal family needed for the movie?