well , you want to have the best ,
and that is not a crime!!!!
as you said , as long you know the value of what Allah gave you , you won't feel that you badly need something , people who are not satisfied with what they have , will be always in poverty "not just material one", even if they have everything.
but being satisfied doesn't mean necessary that you shouldn't look for a better thing , it depends on the cost
you may have good friends , but you want to have more friends , not a big deal!!!
i think looking for better may have problems for "material" things only, as it may have an unnecessary cost .
i have a samsung mobile but i want an iphone , but the cost is too large for "just wanting it".
but for "non-material " things there is no cost ,
i have a headache , and i am satisfied it is just headache not cancer , in the same time i want it to be cured , that is not a greedy thing.
all of us want to have the best and be the best , that is a normal thing , that how we become better and improve ourselves , it is only a problem for material things.