The current Pika Pika no mi is quite underpowered compared to the series' rendition.
Additionally, seeing the new Goro Goro no mi buffs has made me look at the Pika in a different light.

I don't expect anything here to actually be considered, but I do hope some of it does.

(Opinion about the Goro and Pika Fruits [Take it with a grain of salt]: I do think that the Goro Goro no mi should be overall stronger. But I do think that the Pika Pika no Mi should have some advantage over it. Speed and offensive power in my opinion is what the Pika has over the Goro)

I suggest a few things for the pika pika no mi,

Increasing the size of all explosions done by the Pika Pika no Mi in the mod.
Reasoning:
If you look at the current explosion sizes, for abilities like "Light Acceleration", You will see it create an explosion about the size of a charged creeper explosion. But when you look at the anime or manga, the explosions are massive.
Mangrove Tree being chopped by explosion
He quite literally chops a massive Sabaody tree in half.
Or when Rayleigh diverts his attack on Zoro in Sabaody, that explosion is massive too
Rayleigh diverting his attack

I'd recommend watching Episodes 401-402 and 404-405 to get an even better idea. Unlikely that anyone will do this though. E401 truly does show a ton of attacks that the Pika has.

Adding an ability that lets you shoot thin, piercing lasers that don't explode
Reasoning:
This is one of Kizaru's signature moves in the series, I'm not sure if its even a named attack, but I do think it deserves a spot in the mod.
He uses it here Kizaru shooting supernova
He even uses it against Whitebeard Kizaru shooting Whitebeard
Separate the Beam ability away from the current "Light Acceleration" ability
Reasoning:
In the mod currently, the ability "Light Acceleration" matches Kizaru's infusement techniques to "kick at light speed"
However, the ability in the mod can also shoot a laser beam. Now this is mostly just for QOL, but in combat, you sometimes miss an attack. The laser beam attached to the ability also gets rid of the ability for the cooldown. So, it can be annoying to attack and miss, and suddenly lose the buff that you had on your hand/leg.
Spoilers for Manga Add Light Clones and allow the user to reflect off water back into the sky
These are just abilities that he has used, not much reasoning to be seen
Better long range movement/Cooldown Reduction outside of combat for TP ability
Reasoning:
Definitely the most far-fetched one, but basically, the Pika Pika no Mi is literally a fruit that lets one move at light speed. It overall seems pretty hard to travel even just hundreds of blocks extremely quickly outside of combat. My suggestion is that the "Yata no kagami" ability, aka the teleport one, gets a much quicker cooldown outside of combat.

Overall, I just mainly think the Pika Pika no mi needs a rework/buff. Thanks for reading if you did.