If you want a solo fish, the jardini would work for a long time at least, though eventually a larger tank would be better. Jaguar would be cool too.
I've kept solo wet pets in the past, they are cool but unless you really have a special connection with the fish it can be a bit boring.
If you want a community I'd go for an Oscar or two with some other SA fish like flagtail, pinktail chalceus, red atabapo pikes.
Just my preferences, you have lots of options with the 180. The only ideas you mentioned which I don't think would work, would be jardini with tankmates, and giant gourami.