Very excited by the trailer, looks great, the map looks very interesting and super fun, gave me some of those FH3 vibes with the desert, rainforest and coastline. 1 and a half times the size of FH4 is a decent increase as well, especially if they've packed some more road mileage in there as well which looking at the density of roads in the teaser I'd say they've achieved.
Those disappointed with the size, not sure what youbwere hoping for? They've always gone for quality over quantity, yeah things like the Crew 2 are huge, but it's also mostly really boring copy paste stuff. Much rather have a smaller, denser, more detailed map with more bespoke roads.
Furthermore with the disappointment of it not being a certain location everyone wants. Here is my take. PG aren't stupid, they're about the fans, that's why the Horizon games have been so successful and the support for FH4 has been so incredible. They know how much pressure there will be on the Japan location when (and I mean when, because they will do it) they come to do it. My feeling is, because FH5 was always going to be cross gen, they know they wouldn't be able to it justice as a cross gen game. There's a lot that people want and expect from a Japanese location, mountains, touge roads, dense cities, ancient lands, classic countryside etc. They simply wouldn't be able to do what they will want to do with it as a cross gen, they'll need to utilise the faster storage and more headroom of the next gen consoles in a way that a cross gen game simply can't. Mark my words, FH6 will be Japan, and it will be absolutely huge.