nycballer,
If you construct a fake wine review out of chunks of real wine reviews, nobody will notice
A "tight" nose is not at all mysterious. It means that the aroma is not very strong. It's the opposite of "explosive" or "aromatic". You'll also see "closed" for this.
Can't say I've ever seen "round" used for a nose, but when used about the palate it's the opposite of "sharp", basically meaning "intense", i.e. that the flavour sticks out. Examples of sharp flavours would be things like black pepper, lime zest, mint etc.
The use of synaesthetic descriptors - using tactile/visual ideas like "round" to describe flavors - seems strange to you because you're not into wine, but you wouldn't have difficulty with it in other contexts. For example, if I gave you the colours bright red, dark orange and light sky blue and asked you which was most like the noise a trumpet makes, I would be shocked if you didn't say the bright red. If I asked you which was the most "smooth" (as opposed to "spiky" or "sharp") I think you would be odds on to say the blue as well.
As for weird descriptors like pencil lead, people can sometimes go overboard on these things. But the more a wine reviewer can say about the impressions a wine gives him, over time this means that people who read that reviewer can predict whether they will like a wine or not. For instance, I once read a review where a Cabernet was described as tasting like "crushed rocks". I later had the wine and could see exactly what the guy meant and liked that feature of the wine. So if I see that in a review from him again later then I'll think "Hey, maybe I'll like that wine too".