My all time favourite is Tennessee, sometimes there is that moment of 'that texture could look better' but usually it's great for montages
Agassiz speedway its a 1/4 mile oval on a small map so it runs great for me and I have fun in it because go fast turn left
I think that every stock map in Beam has some sort of attribute to it that makes me want to play it (except for Cliff, that's more boring than any other map), but my personal favorite would have to be either Industrial, ECA, JRI, or Utah. (PS: "Decent" for me is about 20+ FPS, great is 30+. Terrible is 10+.) Industrial: Four different tracks, each with several layouts and a nice amount of variety; a nice little industrial rally area for racing around in; and a decent atmosphere and framerate. ECA: Expansive, decent framerate, lots of variety in roads and trails, a great challenge to navigate, a small town, and a really nice highway to cruise around make this a great map for cruising, off-roading, deliveries, and racing. JRI: Tons of variety in roads and trails, expansive, decent framerate, lots of landmarks to travel to, several tunnels, a massive port for rallying, a whole ton of tight roads to race on everywhere, and a runway dragstrip make this game great for off-roading, racing, and deliveries. Utah: Great framerate, massive number of roads to travel on, great rock-crawling areas, a decent amount of landmarks, some cool jumps, a long high-speed tunnel, and an expansive size make this map great for cruising, drifting, off-roading, top-speed testing, racing, and deliveries.
Ehhh...too laggy for me, and it also feels really unnatural. It's almost like it was built around a racetrack, which I guess it was, but that means that the surrounding areas aren't as exciting or as big as they could (or should) be. It's a nice map, sure, but it just isn't all that appealing to me right now.
Cliff is great fun if you go in world editor and triple the scale of everything. Then cliff becomes the size of Oahu and climbing it is actually a challenge that takes some effort and time to accomplish.
I don't know if I'd really be able to pick my favourite out of the default maps... They all have their good bits about them. If you bring mods into it though, then it's the 'Sandy Mountain' map. That's basically where I spend a good 90% of my time when playing this game.