yes, "cohesiveness" is the perfect word for explaining what you meant!
Now, while cohesiveness is nice and convenient, it is rare for only one site to excel at
everything: so, that's why I like to see a bunch of sites that specialize in different aspects of TG16 / PCE universe. Still, I totally agree with you, it would be nice if we had a site like atariage -- or lemon64 (what a kool site! C64 fans take note) -- but those sites take so much work and effort, they only succeed if they get a lot of support.
PCECP is simply an amazing resource for software, but only a handful of folks have contributed reviews to it (or hints / cheats). We could organize a campaign to try to fix this, and make PCECP EVEN BETTER! But I don't know, it would require a high level of committment for a long period of time before it got to the point we'd be really proud of.
The PC-Engine Bible has lots of capsule reviews, which is nice, but I think the wallpaper downloads are the Bible's best "unique" contribution to the Turbo Scene.
Stupid gamefaqs has lots of great info (i.e. reviews / faqs), but its gamefaqs and I will only go there if I'm desperate (i hate the ads, plus I get spyware / popups whenever I visit that site). plus i hate the goddam ads.
Anyway, to sum it up: yes, I totally agree with your sentiments... it would be nice to have a centralized, uber-site. But, we shouldn't put all our eggs in one basket -- so having a loose-knit collection of sites is pretty nice (just bookmark them!)
my 2 cents, anyway