So, here's my rundown:
• Dair and nair have significantly smaller hitboxes and are less useful
• Dair is still a meteor smash, and is the only immediate meteor smash in the game
• Nair still drags down opponents
• Nair can autocancel, which allows lucas to drag down opponents for combos and grabs
• sweetspot bair is harder to hit,
• fair is the same
• Psy effects replace the stun effects from Brawl, which harms Lucas's aerials as they are not as useful.
• D-throw combos into u-air, fair and b-air at many percents
• D-throw to spike bair at 30-70%
• D-throw to u-air is a hoo hah, but can be DI'd due to small hitbox
• d-throw to fair is easier to get and lasts till about 80%
• Pk fire has less range, but retains usefulness, and is semi-spammable
• Psy magnet same, slightly bigger for absorbing energy
• PK Thunder more distance covered (recover from the lower blast-line to the edge of FD distance)
• d-tilt combos into jab combo at any percent
• dash attack is much faster and has two trajectories; tip can kill, mid section pops opponents up for combos at low percents
• Lucas's throw game is OP
• Up throw kills at 100-140 depending on character,
• Back-throw kills, about 20% later than u-throw
• Down-throw is great for combos until 100%
• F-throw is eh
• All do 10%, except for d-throw, which does 6%
• z-air is good, but kind of laggy when compared to Samus or ZSS
• PK freeze comes out faster and is actually useful
Overall, I think Lucas was buffed from Brawl. He can no longer stun and drag down opponents for ground combos and kill set-ups as effectively as he did in Brawl, but he's now got some great zoning/spacing ability, amazing kill options at the 100-130% range, a solid projectile, but mediocre range and little to no means of approach. He can definitely bait out approaches with PK fire and z-air, but characters with solid projectiles like Diddy and Link give him serious trouble.