I remember reading about this. If memory serves, QRP was originally a much more ambitious project designed to replace all textures AND all models in the game.
What about remaking all the maps to have the high levels of detail that would justify the replacement textures and models? 3200 poly monsters in 400 polygon worlds look just as out of place.
But it's all academic anyway, Quake's vagueness is part and parcel of the deal now, and you can't upgrade your way out of it without disappointing a certain proportion of the player base. For example,
this ogre replacement has been objected to on the grounds that he's holding the chainsaw in a hand, rather than it being grafted onto his arm. To some that was a limitation required in 1996, to others the body-horror was part of the appeal (this may explain why Edie is part-ogre rather than part-human).
Similar debates have raged on this board over whether Shamblers have fur or ragged pale skin, whether Fiends have eyes, and whether the Vore has a feminine physique or not (
note to func_ regulars: please resist the natural temptation to reignite all of these below). The more you define the detail, the fewer people will agree with your interpretation. Best to let people's imaginations fill in the gaps, like a good book spared an imperfect film adaption.