New tweak from extended seat post pending - handlebar height!
The Brompton extended seat post definitely gives me a more suitable leg extension (even though my legs are not long and I'm not tall, go figure!) And I now have a little more distance between me and the handlebars, which I like.
But a new problem has arisen. Now the handlebars are too low. I have contacted Grace Gallant in Taiwan asking whether the Flamingo handlebars are closer to the M or H handlebars of Brompton because I prefer to ride more upright. If they are not the maximum height handlebars available from Brompton or third party vendor I will replace them.