My main issue with that first game is that once the protag's clothes come off they stay off. It's kind of boring to have her naked for 90% of the game and also limits the level of embarrassment a character can show. I know ENF has the word "Naked" in it, but theres more to it then just stripping a girl down to her birthday suit and then kicking her out the door. There are subtleties and degrees of humiliation that need to be present for a convincing and erotic experience. I do really like the art and the animated poses though.
The second game I played once when it was first released and it seemed pretty good, I figured the dev abandoned it though.
The last game you suggested is bare-bones... Great concept and artstyle that I would love to see come to fruition, but I have my doubts. It's been extremely slow with all of it's 2 updates.