In terms of the DC TVU i think each show has its own pros and cons but all are fun to watch. Arrow has the drama, with darker issues and villains being taken on. The Flash has the most comic based plot twists, interesting characters and cameos, plus heroic genre based action in terms of cinema to television. Its exactly like a comic new vilian every episode or multiple being faced in a day. Then Supergirl so far has the charm, comedy, and lighter tone. More like a coming of age hero show. Personally im amped up for the Teen Titans show.
honestly Im excited that they are introducing the multiverse. We get some great Flashes from it Wally West, Jay Gerrick and im hopeful for Bart Allen as Impulse. As far as the romance goes Im still an Iris Allen fan