I don't think 290 cfm being a problem, be nice if that was cast numbers and left room to grow built with porters in mind but that's enough cfm for 90+% of people, be nice if port design was geared more to 408 sizes, what's really needed trick flow performance at speedmaster prices anything else is bonus. But trick flow performance with trick prices is a harder sale.
The latest in chamber design would be nice too.
But a bolt on for the magnum blocks without special rockers would be nice, wouldn't mind a set for my 5.9L.