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1. You have whichever batter leads off the 2nd inning the most, presumably the #5 hitter (who you don't select for R scored first; you select him for RBI first). In subsequent innings this "most likely to follow the last out of inning #X" will dissolve into oblivion and not be important.
2. Whichever batters HIT the most (in the whole game) will lead off the most, in late innings -- #2 batter, then #3 batter, etc.
3. IMHO it's not a factor that deserves consideration from the manager's desk, in proportion to other factors (such as getting the most AB's to the best hitters).
Good stuff Anon.