One very good point above(point 2), the other I really don't care about.
The one thing I've been a bit wary of recently is the changes in algorithm to adapt searches to individual people. It filters out things it “thinks” you wouldn't like and because of this surrounds you with a
“filter bubble”.
I prefer having the option to choose what I look at, sometimes random results I'm not really looking for turn out to be the most rewarding. I'd prefer a simpler, universal, ranking system(everyone gets the same results for the same search phrase) and the option to blacklist sites and a +1 button(or like button) to let others know what you think is worthwhile.
@ cheesamp: I prefer the data used in search to be annonamized, I'm also not a fan of data tracking. However I think having the option to view whether people recommend a site is good, it could help reduce the redundant links you go to before finding what you need.