For people who were not always frum or who aren’t yet completely frum, keeping kashrus out of the home is a big challenge involving a lot of sacrifice. People are used to eating out at restaurants and at friend’s houses as one of their main pleasures in life, and much of international travel is about eating new things in exotic locales. Unless the person lives in and only wants to travel to NY or Israel (where there are tons of kosher restaurants), all this must be sacrificed.
Because of the internet, we all have a big challenge both in guarding our eyes from forbidden sites, and using our time wisely. Just think how much more time people could devote to prayer, Torah and mitzvos if they didn’t spend a few hours surfing on the web each day.
Given the extreme cleavages among the charedi, dati and chiloni communities in Israel, I’d say the main challenge there is Ahavas Yisroel and achdus.