Best Level Ever: The climatic race of both games, the Boonta Eve Classic. Long, fast, with the right number of obstacles... It's drop-dead awesome.
Also, the Oovo IV racetracks. Long, twisting, fast, with an epic zero-gravity pipe that can crank your speed over 1000 mph, and it's set to "Duel of the Fates" in the PC/Dreamcast versions.
Breather Level: The Inferno, ironically the very last course in the first game, is far easier than the preceding levels in the Invitation course, especially The Abyss.
All of the Aquilaris and especially Mon Gazza courses in the original tend to be relatively easy. Aquilaris courses contain many twists and turns but are very light on environmental hazards, whereas Mon Gazza tracks are distinguished by many long, wide-open straightaways that make it very easy to gain momentum and keep far ahead of the pack. No accident that those are the two planets completely dispensed with by the end of the second circuit — it's a much harder slog to get from there to the end of the game.
Revenge has a couple more specific examples: The Badlands makes for a needed refreshment after the one-two punch of Watchtower Run and the Brightlands, while Serres Serrano comes at a welcome point after the difficult Ruins of Carnuss Gorguul and serves as your last breather before the much harder last four tracks.
Even Better Sequel: While not as remembered as the original game, Revenge took an already excellent licensed game and substantially refined the gameplay, physics and speed mechanics—it helps that it was also produced by the same folks behind ATV Offroad Fury. The most persistent complaint is simply that there wasn't more of it: with fewer pilots, half as many tracks, and only five distinct planets to the original's eight, the overall feel is greatly scaled-down. (Plus, the number of contestants per race is reduced from twelve to eight, although you'll certainly engage with them much more than in the original; meanwhile, the tracks are usually shorter, but they also recycle material less than the previous array of tracks.)
Game Breaker: Sebulba's flame thrower. If it hits someone's podracer, it shall make one engine burn, then get destroyed, and finally making the whole unfortunate podracer explode. Hello, curb-stomp race!
Good Bad Bugs: In The Gauntlet course, if by chance you decide to race backwards from the ending tunnel back to midway through the course, a racer will be stunned to find that more than half of the course has vanished (but is largely playable, aside from the heightened danger of falling off)! Fortunately, going as far back to the start as possible will allow the vanished course to reload.
Most Annoying Sound: "Bullseye" Navior and Neva Kee have very shrill, exasperating voices in the original, though the voices do match up well with their designs.
Revenge has a few examples. Tom Kane seems to have voiced fewer lines than average for Shrivel Braittrand, or else fewer of them made it into the final cut; either way, you're going to hear a whole lot of "WUMPITY WUMPITY!" when racing as or against him. A couple of the pilots also taunt you with some truly Annoying Laughs as they pass you up, such as Knire Dark's singsong, sarcastic "Ha. Ha. Ha. Ha." and Wan Sandage's incredibly drawn-out belly laugh.
No Problem with Licensed Games: The game was a critical and commercial hit for a reason; this game actually shows care and interest with a wide selection of drivers and creative track designs. The upgrade system also isn't a slapdash concept. You can even play the game two-fisted with a Nintendo 64 controller in each hand to mimic the twin-engine controls of the pod racers in the movie. Revenge was also very well received.
Polished Port: The Sega Dreamcast port of the first game; while the graphics are almost identical to the Nintendo64 version, the framerate is much smoother and the textures are much crisper and slick looking, and the sound design and music quality is no longer hampered by compression issues. Mini CGI cutscenes are also included in the start of each race. The only trade off to the port is the addition of loading times.
Scrappy Mechanic: The part damage/repair outside of level concept of the first game. During races, taking damage or crashes actually effects the podracers performance stats in real time, which really undermines the part purchasing concept in a game where its ridiculously easy to crash or suffer collision damage. While you can buy pit droids to fix your pod inbetween races, it takes time for their work to take effect, and only four parts of a pod can be fixed at any time. The sequel thankfully eschewed this mechanic, by allowing you to keep your pod upgrades permanently upon purchase.
On the flip side, you can also use this to your advantage by buying high-level but damaged parts from Watto's junkyard at a fraction of the price you'd normally pay for them (and possibly earlier than you'd normally get them, too). Then, if you get through the race unscratched (or you have invincibility turned on), your Pit Droids will have fixed the junkyard parts up to their full potential. You can then either keep the parts or trade them in for a profit and repeat the process.
Scrappy Level: Grabvine Gateway; it's not a difficult level by any means, but it has some really tricky turns and cluttered pathways, particularly the swamp area late in it, where it's almost impossible to avoid crashing when you're racing at full speed.
That One Level: The Abyss, easily the hardest course in the first game. While the bulk of it isn't that hard on it's own, the one part that makes it so frustrating is that if you don't stick to the top path of the course (which is very hard to do without falling off), you have to take a much longer path back to the main track, and this will set you far back behind the other racers.
In the sequel, the Nightlands of Ryloth is often held up as the equivalent, with many players online having bemoaned the fact that it's harder to beat than the Boonta Eve Classic which follows it. However, from the perspective of knockout completists, Gamorr's Watchtower Run has reached consensus status as That One Level. It's such a short track that you're under enormous pressure to rack up the seven knockouts in time, with the final attack on Aldar Beedo usually coming down to the very last stretch of the track. Accomplishing this with a non-secret character is a mark of true Podracer-brawling skill.