I've been on holiday or I would have leapt in earlier.

I play MacCann duet, and I find it GREAT for morris. I can get a really good dancey style. Most morris tunes are in G, D, A minor or E minor which are all easy on the MacCann.

To say the layout is illogical is largely irrelevant (- presumably you posted your comment on a 'qwerty' keyboard !!) In fact playing chords is a bit like on guitar - each chord is its completely own shape and you just learn them. After a time I found I hardly have to think about the left hand end, apart from choosing which chord I want.

Most morris concertina players seem to use anglo, probably for historical reasons. Many people will tell you it only sounds right on the anglo, but that's because that is what it's usaually played on.

I love the English concertina, but it doesn't encourage a dancey style like what you want for morris, but no doubt it can be done if you try.

All the best with whatever you end up with. By the way, anglo is probably easiest to play standing up.