I calculated 7 of the 8 things you asked for, and you can see the results below (the straight + flush draw has too many iterations for me to wanna take the time to calculate right now. I might come back to it later, but for now here's the rest).
Someone can double check my work, but I got to 9.4% not including straight + flush draw (although I'd guess that if one pair + fd is 1.6%, then straight + flush draw is probably somewhere in that ballpark).
I don't quite understand your betting question. Is the bet that you put up 15 against 100 to hit one of these flops with 78s? If so, then it looks like you're probably losing a few points, depending on what the straight+fd actually comes in at. Let's just say the latter is 1.6%, bringing your total expected flop pct to 11%. That would mean your EV on the bet would be .11 * 100 + .89 * -15 = -$2.35.
The house always wins.
Last edited by mkind0516; 09-26-2018 at 10:44 PM.