My first impressions are surprisingly underwhelming...
The framerate doesn't feel as smooth as the main game. I find this surprising considering how open and minimalistic the new map is at a glance. Blizzard Mountain has framerate issues too, but there it hardly affects the fun like it does for Hot Wheels. Loops, boosts and jumps simply lack the thrills when the accompanying frames don't satisfy. Very noticeable framerate drops too, which is new for the Xbox One version of FH3.
The tracks don't feel like tracks. I expected more room to go wide in the sharper turns, more cambers working in our favor and more spectacular points of interest. I can appreciate the difficulty in learning the quirks of the new network, but I can't help thinking they missed an opportunity by not letting players drive without the care and consideration required in the main game and on Blizzard Mountain. This map roughly feels like another bunch of roads camouflaged and spiced up with Hot Wheels characteristics. Also, boost pad placement is too random at times as some race routes require hard braking just after running over a pad. Nor do I like how the boost pads often send the revs straight into the limiter until shifting up two gears or so. Again not very satisfying.
It's too easy to beat the AI. I've played on the second highest difficulty level for months now. It has been demanding in the sense that skill and consistency pays off. However, in Hot Wheels I can drive like an idiot and still win by far. Keira did mention that my victories in Thrilltopia were like child's play and how that seemed appropriate. Well, I disagree. It shouldn't stop being demanding just because Hot Wheels is involved. I can't see myself bothering to finish the campaign if it doesn't challenge me more than it has done so far.
The new islands are rushed. I decided to explore the beach outside the autoshow and came across some "sand dunes". Unlike the smopth and curvy dunes known from the main game, these ones were rough and sharp like rocks. It comes across like auto-generated mesh with nothing but familiar textures applied on top. More polish please, but I suppose it's too late for that.
As a final remark, hot fixes are needed for some small things not working as intended. This is to be expected these days, but I think Blizzard Mountain got more things right from the beginning, at least for those players who could get there. I'll keep playing with an open mind, but so far it's not living up to the hype generated by the announcement trailer.