My hope is whatever engine the 4/4 ends up with it retains its lively, keen to rev zesty nature. The nimble handling and light weight aided by such a gem of an engine are what give character. Its character that helps us forgive little things like drafts/leaks and suspension "shortcomings".
The Mazda MX thing would be a worthy donor of its brilliant 1.5 skyactiv power unit.
But I think its going with the Mondeo lump instead. Not sure how Morgan will market the 4/4 and plus 4 but no doubt they will have a plan!