I have more memorable strips of road and fuck-around areas in the first game, and didn't really take to the large open grassy areas in FH2 but that's definitely subjective. The off-road trails were more fun to tackle on their own without worrying about cars cutting right across those trails and t-boning you. The observatory, red rocks and cliffside racing, the farmside paths with the overhanging trees, the quarry, and the warehouse districts and small towns were flawless little areas to drift and generally just hoon about. There's a lot to love in that first game.
In terms of visuals, FH3 is what I would expect from an Xbone version. There are plenty of moments in FH2, like driving on the highways and lonely roads with civilian cars that look last gen. FH2 really shines when hightailing it through the grass or in storms.
Am not here to shit on a game I truly love, that's just how I felt from the get-go. FH3 is really exactly what I was hoping for on new hardware. It has that wow factor the original game had on the 360. Just took Playground some time to get used to the new hardware without worrying about last gen.
I'd still recommend FH2 for anybody who wants an open world driving/racing game without a doubt. Its still one of the best open world racers ever made - I just still hold FH1 a little fonder for its map and focus on roads over large open fields.