Honestly, every single new art looks better to me. And Watery Grave has my favourite Magic land art ever.
I can see people liking the old ones for nostalgia reasons, but the new ones are better drawn. The closest one has to be Blood Crypt for me, I find the new art kinda boring.
Yeah, I agree with you but the old ones aren't just "boring" and the ones aren't really "better drawn", they're more realistic and less fantasy. I see them more as what they would look like in a realistic megatropolis, whereas the new ones are more like what they should look like in a MtG fantasy game.
Also, the old ones are more like an example of a forest/plains (or whatever) in a cityscape environment. Whereas the new ones are more like fantastic magical guildhouses, which further reinforces the stronger guild feel of RtR as opposed to Rav.