But also, Hellsing is completely silly and stupid and is merely a dreamlike splortchathon with nonsensical plot twists and excuses and hilariously pompous monologues, so 1) I don't see how one could see any fault in that, it's simply glorious, 2) I don't see how one can nitpick graphically on that, it's not the sixtine chapel, it's cheesy vampires repeatedly exploding each others and (for some reason) themselves (for some reason) several times in a row, 3) the OVA is a bit too self-serious when it comes to that, with its almost genuine attempt at edgy vampire nazi horror gothic philosophical drama, and in a way I had more sympathy for the original's lighter nonsense - it's a healthier brand of cringe (apart maybe for the random lesbian licky seduction, but that's just a spike of cringe in a generally cartoonisher cringe than the OVA's gritty nazi cringe), and 4) most of that video's complains apply to the OVA because it's just the definition of Hellsing (the OVA is barely more coherent, and its delirium monologues are even longer - shut up Major we got the point with the first sentence).
Also yes, the original goes completely off rails as it catches up with the manga, and that's usually a disastrous situation (Gantz, Game of Thrones, etc), but given how equally stupid the manga is, it's hard to argue there's a genuine narrative loss there.
So I stand my point. Both versions are nonsensical fun, one is brighter and more cartoonish than the other that takes itself more seriously. But both are dumb as hell, and separated by a slight nuance in tone. In my view they complement each other well, and I don't think I would have enjoyed the OVA that much without the semi-unintended humor of the first version.