My thoughts (Possibly Spoilers)
I wanted the MC to use wishes in a smart fashion ....
he will first wish to swap bodies with Majin Buu , like Zamasu did with Goku ...
(I believe this is within Kami's ability , as majin vuu is actually on earth , and soul swappin us just a magical technique)
(Note: This will have the added of benefit of when Babidi comes to revive Majin buu , he will get a majin buu in Oolong's body , who can be easily killed ....
although the majin buu will still keep combat experience & energy that babidi injected , he won't have devouring abilities , transformation abilities , regeneration ...etc)
Also , Although the MC would gain Majin Buu's body as his own , he won't have majin buu's power ....
he will just have majin buu's innate abilities ...
this is because , in the original , Babidi had to inject majin buu cocoon with a lot of energy to revive majin buu ....
So , The MC won't be OP instantly ...
He will still have to train ....
The MC , in the next year after that , will gather the dragon balls again , and wish for the All knowledge about martial arts & Techniques & science of all ages & times & places that the dragon can acquire ....
The MC will then set to train for some years ....
while occasionally going to gather dragon balls and wish some useful wishes ...
When Piccolo (The old evil one) is defeated , The MC will absorb his body to gain super Namekian abilities (Magic Materialization , Gigantification , Healing , instinctive spirit control , Greater control of ki & magic , creation of offspring , Dragon language ...etc) & Eternal youth (if he didn't already have it as majin buu)
When Raditz comes to earth and is defeated , The MC would absorb his body to get Saiyan abilities (Zenkai , ability to create S-cells , Oozaru transformation , greater affinity to martial arts)
When the Drafon fighters go to Namek to fight Frieza , The mc would go with them ....
He will absorb the Ginyu members when they are defeated ....
He will also absorb Frieza before the planet explodes ....
After that , He will travel to Yardrat , and stay there while training in various techniques , and the new abilities he got (like guldo's ability to stop time) ....
He will also try to perfect his Ki control & spirit control ....
so he can have god ki faster later on .....
(the knowledge implanted in his mind doesn't actually allow him to use the techniques instantly , he will still need to train them)
He will only return to Earth after the Androids & Cell are already created ....
He will absorb Dr.Gero & Android 20 ...
He will also absorb Perfect Cell ....
Then , He may continue getting various wishes ....
While not neglecting training & trying to acquire new techniques & magic ...
He will also roam the universe for a while so he can absorb various races with unique abilities ....
He will then continue getting stronger , and will create some offspring using the unique method ...
(So he has children who are in the age of Gohan & Goten & Trunks)
He will then try to gain God Ki , and to fise his various transformations & skills ....
when SDB begins , He will be very strong ....
He will fight Beerus to a stalemate ...and try to comprehend Destruction energy ....
he will then take part in the tournament between universes 6 & 7
He will take part on the fight against Zamasu in the alternate universe ....
he will absorb Fused Zamasu to gain Immortality on the level of soul
(he can fuse his soul with the universe , and recreate his body after getting enough energy ....
the only way to kill him then would be to destroy the entire universe ....)
He will later take part in the tournament of power & smash it with force
(while also absorbing contestants in the process ... they will be revived anyway after the tournament)
Later , He will absorb a bit of Broly's blood , to gain the legendary saiyan transformations
(He will be able to do such a thing only with Broly , because he already absorbed a saiyan , he only needs to mutate the saiyan abilities inside himself)
He will later fight & absorb Moro ...
after that , He'll fight the evil demonic time-travellers , and absorb them ....
In the end , He'll absorb Zeno who got corrupted & became evil (somehow) ...
and he will absorb both zenos , and he will become the supreme king of the Dragon ball multiverse ....