Personally, I don't like wonky shots but that's a matter of taste! However, the first shot is also very soft due to camera shake and poor technique BUT the good news is that the second shot is plenty sharp enough so practise has helped your technique to improve (I see they were taken about an hour apart, so you had probably taken a few in the meantime). I find that my shots improve through a day at the races - I don't shoot motorsport that often so my panning skills deteriorate between sessions so I try to practise during early sessions on less interesting machinery so I'm more up to speed when there's more of interest.
As for the tight cropping, I usually leave a fairly loose crop which allows a fair bit of compositional fine tuning. Not the "correct" way to go about it but it works for me, especially since I use the central focus point since it's generally the fastest and most accurate. Of course, you were at the shortest length available on the lens you used, so maybe a shorter lens next time (if you have one)?
Shutter speed's about right, fast enough to avoid too much shake (on the E-Type) while slow enough to blur the background and the aperture was small enough to get plenty of DoF. Keep at it and always remember that the Mk 1 eyeball is as good at capturing memories as any camera even if the memory does fail a little over time! A combination of eyes, ears and nose is as important as a camera.
I would have been happy with the E-Type shot as a first attempt and not too discouraged by the top shot either. Keep at it!