What’s more fish safe?

[i cant think]

Okay, I’ve been wanting another invert in my tank for a while, I went to my LFS and saw two inverts I like. Food isn’t an issue for one of them.
One was Alpheus randalli, and I have a yasha goby I’d like to try pair with a Randal’s pistol shrimp.
The other was a Mespilia globulus, I have 2 large urchins (White pincushion - Lytechinus variegatus). Getting them algae isn’t an issue, I have dried nori for it to eat.

The issue is, I have a miniscule goby - Discordipinna griessingeri. They don’t get over 0.75-1 inch long so my worry is that I add an invert and it has an expensive meal. Which one is less likely to do that?

 

[Hoodstream]

I think urchins are definitely capable of eating small fish as well as a pistol shrimp but the pistols are opportunistic eaters and would only attack if the fish is already sick IME