Road to riches has possibly become even less necessary than it used to be since surface mapping became a thing.
Because you can now make such high volumes of credits by surface mapping ANY earth like/water world you come across you can simply open your galaxy map and filter it by economy/agriculture. Then bounce around agricultural systems mapping all the earth like & water worlds.
For example, I’m in game now and I’m about to do just 5 jumps to agricultural systems.
Jump1 = 1ELW
Jump2 = 1ELW + 2 terraform HMCW’s
Jump3 = 1ELW + 1 terra
Jump4 = 1ELW
Jump5 = 2ELW + 1WW (Jackpot)
These aren’t even big jumps, just 10ly hops. I’ve probably just flown past 7-12m credits worth of data, in 5 mins...
So, not quite what you asked for. But very quick to do.
A more organic way to do this (stops you getting bored) is to make a simple single cabin passenger ship and focus on VIP transport.
‘Transport’ missions will have you go from one star port to the next and they have a very high tendency to be orbiting earth like worlds all over the bubble.
So as you’re slowing your ship to drop your passenger off you just pause a second to do your surface mapping.
You’ll then get payed for your mission and get a very hefty exploration bonus on top!
Edit: For fun, I just mapped the two earth likes and their moons at Fulastobo. It was worth 8.5 million credits.....just silly money.
FD could honestly put the price of the new detailed surface scanner up to 20million credits and it would STILL be worth it.