Thank you @Schaick - it still needs a fair bit of work, but I know where I want it to go, while still keeping the tune recognizable !  Another few hundred play-throughs and I'll have it the way I want it -

Thank you @Fran - and an interesting observation - that's exactly what I was intending - almost as if there was a slightly out-of-phase "counterpoint" - or some type of "melodic echo" to the basic melody, without actually double-stopping all the way through....   but - well - I was just experimenting with it...   let's see how it finally turns out...