Nice!  Never seen it all laid out like that before...

A few others I can think of  -

At first Marty's sister is unpopular, then at the end is told by the brother "hey, I can't keep track of all your boyfriends" or some such.

The scene with Jennifer in the town square is completely crammed with setups - in addition to the clock tower flyer, there's also:

Marty sees the 4x4 truck, later he will own it.

Marty frets about sending his demo tape to record companies, and Jennifer says "Like Doc says, if you put your mind to it, you can accomplish anything".  Marty answers with "what if they say I'm no good?...  Jesus, I'm starting to sound like my old man",    Later George says the same thing almost verbatim about his writing to Marty, and Marty gives him the "put your mind to it" line.   Which George then echoes again at the end, talking about his novel - "It's like I always say, if you put your mind to it..."

And the demo tape itself is a setup - (I believe) it's the same tape he later uses to melt George's brain.   (I admit I could be wrong on this one).

EDIT - oh, you had the 4x4 in there already, I missed it.   Carry on.

I'd agree the act break comes when Marty has gotten his parents to fall in love, and the final act is all about getting Marty back to the future.   

I think that makes the actual break Marty's final scene with his mom in the stairwell, where we find out for sure that Lorraine has chosen George.   Once that's settled, we immediately cut to Marty meeting up with Doc at the clock tower and the race to the finish is on.

What, you mean that kids movie with Huey Lewis in it? Oh, sure, THAT sounds like a rock'n good time...