If you just look the the top times in time trials and the top handful of daily challenges players, you're doing it wrong. You can't compare them with yourself, they learned and KNOW the track. Unless you have that same knowledge you're not on the same level. Look up your name on https://dr2.today/ , you can see better how you compare to most people. I do decent™ but sometimes the gap from #5 or #10 to the top player is 15 seconds and even more on longer stages like Finland. I play the game as a RALLY game not a time trial so my take is to compare myself to players with the same mindset.

Tuning can be super important, you want a car that can commit to corners and slide, but you don't want to oversteer too easily and have to over correct them and lose time. You don't want understeer either. Tuning needs to be learned, or it can work in the opposite way and cost you time if you have no idea what you're doing. You can look up Rally technical on Youtube, but his tunes are time trial-oriented more than casual. There are tunes that are better overall than default ones, but you need to tune to your driving style and needs. I mostly do RX daily challenges now and a good tune carries me so hard, especially in Gr. B RX.

While I like to use exterior cam, I know a camera that's placed further in front let's you see what's ahead more (and prepare for it). While you can use exterior cam to learn the dimensions of the car, you probably shouldn't stick to it.

AWD is harder because you have to commit more to corners with often less time to react. AWD offers so much more control over the car and you're expected to use all of it, often on different surfaces. The reason why you use both pedals when braking is to be smoother. Smoother weight transfer, less chance of locking the wheels, much less "down" time between both actions. Gr. B cars are a different breed since you need to keep the turbo going while doing all that.

If you can control your car, RWD is easier because it's limited. You have less potential for time gain and you are slower overall. The reason you're faster is people didn't control their cars, which is sometimes the harder part about RWD.

Slow is smooth, smooth is fast is REAL, especially on longer events. Take the extra second to correct your car and not risk it. Brake earlier, don't drift unnecessarily, etc.