On mobile so I'm not going to quote every single phrase in response to the Lucas v Oli MU. I definitely dont think its unwinnable, but Oli has to work hard at it.
The fast faller combos I'll lab out later and see how they work firsthand unless someone has vods showing them in-game.
To give a general rundown of Lucas' combo game on Oli / similar weights:
DJC / PKF links into itself, magnet, Down / forward tilt, grab, Nair, Dair, and PKF from 0 to ~25%
Dthrow:
0-25%
- Fair (DI behind) -> regrab/aerial
- Uair / Utilt (no DI) -> Uairs / 1 more Utilt -> Uair / Fair
- Bair -> regrab / magnet / Utilt
25-70%
- Fair (DI Behind) -> Fair / Uair strings
- Uair (no DI) -> Uairs / Fair if they start to DI Uair away
70-115%
- Sweetspot Bair if no DI
- OU Upsmash (no DI) / DACUS (DI behind)
- Uair (no DI / slight DI behind) -> Bair
- Fair (DI behind) -> Bair or Uair -> Bair
> 115%
There's also some oddities with dash attack and magnet mixups
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As for PKF vs Pikmin toss in neutral, it appears that you all assume Lucas will be standing still and taking these pikmin to the face for free while PKF is helpless. Grounded PKF out-ranges pikmin and DJC PKF is still better if it hits Oli than pikmin are hitting Lucas. Yes, not all the pikmin will die when latched onto Lucas, but he can still run up and attack through the Pikmin despite Oli's short WD back. Stop thinking in terms of hitlag frames and think realistically about approaches and defensive options. Hitlag only means the frames are out for longer and if an enemy character is in hitlag, they have the ability to SDI during that time. It doesn't mean "welp, I'm unable to do anything now."
I think that Lucas v Oli defines good offensive character with average defense meets defense character with average offense. Their styles in neutral are similar: use projectile, get grab, do combos, meanwhile they have similar weaknesses: easily juggled, telegraphed recovery, tether grab.
The defining points to me lie within Lucas' strong mixup game, ability to control stage very well and quickly change the tempo of a match (even when up or down a stock), and access to kill setups / high kill power.