In additions to the ones linked, there were two street scenes suggesting a Maria -David relationship. Both involved Oscar.
In one scene Oscar was telling Maria "but what's all this 'David! David! David!'"? Maria tried to explain to Oscar that it sounded like he was jealous. (I wonder if the writers had "Marcia Marcia Marcia" in mind at the time?)
A year or so later, Oscar was trying to get Maria to argue, since that's the kind of activity he enjoys, heh-heh. (I don't think this was the episode in which he started "Oscar's Argument Boutique") Maria refuses, explaining that she really doesn't like to argue, and how there are so much nicer things in life. However, her message goes out the window when David shows up, apparently late for a date, and she shouts "WHERE HAVE YOU BEEN? I HAVE BEEN LOOKING ALL OVER FOR YOU." Maybe Oscar was jealous yet again, that she'd argue with David but not with him. The argument resurfaced during the closing credits, after the picture of the CTW logo was already up
MARIA: I TOLD you they wouldn't let you in after the movie started.
DAVID: I was WORKING.
MARIA: Oh sure, sure. (in a sarcastic voice. "Oh sure" was a common idiom at the time for when you didn't believe someone.)