Hope it's not too late yet:
V4P3 ~43%
[...] with the other Rogeubert sailors, [...]
should be Roguebert.
~52%
[...] some kind of liesurely cruise?
should be leisurely.
V4P4 ~63%
[...] he came from the from a family of knights [....]
"from the" is duplicate, kinda.
~67%
"Lofus, not everyone like black coffee," [...]
should be likes.
V4P5 36%
[...] reproduce, leaving to even mightier mages.
should probably be leading.
~45%
[...] they had beene on the worst of terms
should be been.
~73%
[...] among thecream of the crop [...]
should be the cream.
V4P7 ~26%
[...] between a marquess and a duke's house.
Two things feel odd here. First, it should probably be a marquess' or marquess's - Lofus is not yet head of his house. Second, while house appears possible, I'm not sure if the heirs to the house can be considered speaking as the house - maybe it should be just that, heirs instead of house.
~30%
[...] lifed a life of isolation.
Should be lived.
~48%
[...] killed. the entirety [...]
should be The.
Also, just as a comment, the gender neutral version here reads weird as it jumps from the singular "the magistrate was" to the plural "they were".
~52%
[...] the evil magistrate and auditor was executed [...]
Weren't these two different persons? The jobs would usually be opposite to each other.
~57%
[...] staunchly loyal to Luens [...]
Should be Ludens I think.
~61%
[...] Lofus continued to spend his days in bliss [...]
While I'm sure that ignorance is bliss in this case, is it a common shorthand? Because I doubt that his daily life is bliss...
V4P8 ~18%
They were quickly repelled away.
I'd remove the away. It makes no sense together with repelled.
~55%
"Ah, revenge for someone close you,"
Misses a to.
~73%
[...] for the prestige.I'm the odd one out [...]
Misses a space after the period.
V4P9 91%
[...] compatible with holumagic [...]
Maybe holy magic? I can't be sure this is not some weird play, but...
And indeed, she's has shown us [...]
I really prefer the has over the 's, but one needs to go.
~96%
Just because she's very compatible with holy magic, it's not like she can do much anyway.
That sentence needs rewording, e.g. Just because [...] does't mean she can or Even though she's [...] it's not like or something along that.
~100%
[...] at all, but Lofus, uses it as easily [...]
The second comma shouldn't be there.