Back now- TLDR: Some good/bad but overall a bit meh!
I've attached my route below, I only used small A-roads as I only felt confident pushing on with roads that had a central white line and most B-Roads are way too narrow (example pics below).
Started at 7am after taking an hour to get there. I left Tunbridge wells heading south and it took about 2hrs to complete with a toilet break at the halfway point.
Road 1 was quick but boring.
Road 2 was 40-50 until a very good 1/2 mile twisty section right before the end.
Road 3 was fun with a downhill wide switchback.
Road 4 is straight, fast but undulating so you can't see very far ahead.
Road 5 was great (2nd favourite).
Road 6 is awful, just dire with tractors, traffic, police, 30mph villages every 10 yards etc
Roads 7 & 8 were transit roads rather than part of the route. Wide, fast but boring in the main.
Road 9 was good but short.
Road 10 was another transit road, OK.
Road 11 was fantastic, easily the best road of the day by a mile. It even had 2 places where you could see the scenery rather than hedge rows/trees.
Road 12 is half good (vertical off Road 11) and half way too narrow (east into Tunbridge).
I'd like to do it again but try some of the other roads around the West side of Tunbridge as these seemed better but the hour commute is an annoyance. I'd also like to find some places to take a few pics but the roads today were all covered by hedges/trees etc so you saw nothing except 2 bits on road 11.
Overall - A bit Meh! Yes there was a single good road and I'm sure those who drive there regularly can tell me of better ones to use but the route I picked via Google Maps was a bit naff TBH.
Small "A Road" which I like - Central white line, wide enough to two cars easily etc
Narrow "B Road" wide enough for 1 car or 2 passing at <10mph