Here's my fastest times and highest scores for World 3 of SMB 3D.
Stage 1: Chocolate Bar (52.46) - I think the execution was great here. The first jump is hard to pull off.
Same Level (5953) - Not sure about which bananas you should collect to get the highest score possible. I did pretty well with this strategy.
Same Level - Funny finish
Stage 2: Milky Butterfly (56.80) - It's very rare that you'll be able to get over all of the walls and jump straight to the goal. I tried for an hour to get this and am happy with the result :)
Same Level (6130) - You have to be very precise to make that second jump without falling off.
Stage 3: Switch Bridge (48.30/6330) - Good I guess.
Stage 4: Smooth Whip (42.10/5710) - Meh...could be improved, but this stage is not interesting...
Bonus: Banana Love (38.30/8860) - Fun bonus stage!
Stage 6: Cake Dive (56.36/6436) - A very annoying shortcut. My favorite part is the ending :P
Stage 7: Knife and Fork (54.55) - Fast
Same Level (7745) - I'm not sure if getting that second-to-last banana gives you a better score than if you didn't get it. I might test that in the future.
Stage 8: Flower (44.96/5896) - Could be improved a tiny bit.
Stage 9: Bumping Saucer (54.86/6986) - A stage where waffle12996 and me had a long war on. The WR went from 6853 (CloudMax) to 6910 (me) to 6935 (waffle) to 6940 (me) to 6953 (waffle) to 6965 (me) to 6975 (waffle) and finally the 6986 here.
Stage 10: Safe Sugar (54.06) - Looks pretty cool.
Same Level (6950) - The first part (where you bump into the red border) has to be very precise.
Aladdin's Castle Improvements:
2-4 Large Square (7451) - WR went from:
2-6 Square Wheel (6533) - This strategy underwent three different variations before the one here (which is ridiculous). WR went from:
2-8 Mini Slider (7200) - Fun strategy! :D WR went from:
7018 (me - new strategy)
2-9 Leaf (7040) - Ugh. Every part of this has to be perfect to get a time like this. WR went from:
As you can see waffle and me are very competitive. Kudos to him for beating me so many times and helping me get better at these stages!
All of these are WRs at the time of uploading.