Stansted, A120 to Puckeridge, A10 Hertford, A414 Hatfield, A405 Bricket Wood, mainly dual carriageway and you’ll miss the nasties.
Could be worth returning by this route but continuing on the A120 at Stansted and linking up with the A12 at Marks Tey, only problem there is Macdonalds roundabout at Braintree at that time of day, I was stuck there for half an hour on thursday due to a broken down lorry.

Haven’t been to the Suffolk Show for years, 1977 in fact, the company I was working for then had a stand as they were involved in farm management, I had some of my nicely coloured plans on display but didn’t get a single enquiry, even Princess Anne walked past without a look.
I had to swelter on a hot day in a jacket and tie as well, in the end our surveyor and I gave up and we got pissed out of our heads on Abbot Ale, how the hell we got home is a mystery, I have a vague memory of ending up at the worlds smallest pub at Bury St Edmunds, The Nutshell? then falling asleep in a field somewhere in the wilds of Suffolk. The boss wasn’t impressed, good, miserable old sod, served him right.