I have noticed that many of the 4-5 star Unity games are rather large downloads, and rarely have a compressed alternative. So, I would agree that Renpy is better when it comes to file size. Renpy games also allow skipping already seen dialog, so playing thru a second or third time is much quicker. Although, RPGM are probably the worst when you want to play thru a second time, so save often for those. Although I agree with you, I have to respect the developers choice because there are several great Unity based games that I would put in my top 20.