I'm not involved with Hibernaculum, but Vic is a friend, so I figured I'd weigh in.
I find this line of criticism of his work is unconvincing. On the moral side, he's not stealing assets and he's not secretly assimilating the work of lesser-known developers or something. On the practical side, Vic's art always composes a seamless stylistic whole that all but guarantees that he must transform his source materials in the process of folding them into his work. Finally, as to the criticisms about overpainting or borrowing inspiration, to me a lot depends on the vision that goes into selection -- that is, setting aside the moral and practical points just addressed, the quality question to me is whether the artist/writer/designer/composer is drawing from tired, commonplace sources or whether the selection reflects a roving mind and a sharp eye. It is just far more likely that a work will be novel and additive if it is drawing from (say) Waxworks, Bitmap Brothers, and Golden Age scifi than if it is drawing from Games Workshop, Blizzard, and George R. R. Martin. The resurrectionist who brings back something glorious, beautiful, and almost forgotten from the past does something really different from someone who puts trendy clothes on a familiar model.
Finally, while intellectual sparring on forums is great, and does sharpen a developer's craft, this strikes me as less likely to provide Vic useful advice and more likely to risk disheartening a successful artist and derailing his popular project, which is in nobody's interest at all.
Anyway, I'll leave the thread again to those whose project this is, but wanted to say my bit.