I'm trying another 2 batches of eggs, one of which had wasps emerge and the other batch only 4 still alive. My choice of miscellaneous plants is very hit and miss, mostly miss.

glad i got it right

And I just figured out why my new batch of nymphs are dying off.
Wrong food options.

No I don't. And I didn't save (freeze) it either.
So next time, if there is one (previous efforts have been unsuccessful), save one adult for more photos or at least get a ventral photo?

OK, any general information on what to feed, what to do, to keep them alive? I know, one size doesn't fit all. These did seem to prefer older forage rather than fresh.

...and quite a few other pentatomoids
accurate size measurements may also help a lot -- though probably not in this case

Actually, it seemed like you must have done pretty well to get any to adulthood! What kind of stuff were you feeding them? I know a lot of species seem to do pretty well on beans. (I'm actually doing a little bit of experimenting on some Pentatomids that I've caught myself right now.

And yeah, for the future, I would always try to get a ventral shot of stink bugs for identification if you can. It's not always needed, but there are quite a few species where it can be crucial or at the very least it can help to confirm an ID. I think this might be E. tristigmus (but I'm not confident enough with this genus to say for sure yet). I know Vassili is pretty good with them though, and at least in the midwest there aren't too many options, so there's a decent chance we can get this to species.

I'm planning on trying to do a bunch of rearing of (mainly stink bug) nymphs I come across this spring, we should compare notes!

smorgasbord of nearby, easy to collect plants, flowers with some greenery. I'm not sure what they would have preferred but of the choices I gave them, Dandelion and Red clover seemed suited. I gave them fresh every so often but they almost seemed to prefer the slightly declining ones already in the jar.