I'd do a life myself, I'd make it post-metallic, post-silicon, post static: I'd make it use water and carbon, so that it can exist everywhere. I would make it so that it can become intelligent on a small time scale, say a few billion years, all on its own, from scratch, on any rock :D
Not saying we have an engineer, but you think of engineered life as you are now as a simple software programmer. But an engineer in 500k years trying to expand more, would probably think of chemical automata that can evolve and adapt in harsh conditions. Say for instance if humanity decided it would be enjoyable for life to exist on Jupiter. It'd have to make something that can try a lot of variations with a very simple first formula to consume whatever gas there is there and survive whatever pressure.