As for the word Baka: I think it depends on who says it and in what context: I would definitely expect it from the Weebs, since it fits coherently with the personalities of the two. From Lucy I could only imagine it fitting when the MC possibly starts to date the two and she teases him a bit.
As for the bulge issue: I strongly assume that it's all about the quick fap and for the developers, if you can call them that, it's about the quick buck. But since the graphical quality is almost always lousy, I ask myself: Why play something like this when finding porn is much faster? My only explanation is too much money and a penchant for masochism.
For me personally, such games are the Michael Bay movies of this genre. Breasts in focus, a lot of wiggling around and nobody has the slightest idea what's actually going on.
I think the problem is also that some of the better games are more sophisticated in their writing. What are the characters' strengths and weaknesses, what is their philosophy of life? Another problem might be the question of where you want to go with your story? It is very easy to write yourself into either a dead end or a writer's block. Not to mention potential holes in the plot that you don't notice until it's too late because you can't see the forest for the trees. Not everyone is born to be a writer, but if you still want to try, you should definitely get other people on board who have a different view of the matter and can inform you objectively if something doesn't make sense somewhere. Here is then again the problem that either the writer could not be able to criticize or surrounds himself with yes-men who only say what the writer wants to hear or the criticism could be brought forward absolutely unobjectively, of which the writer also has nothing.
MNM is very good for me so far in terms of writing style and you can tell that Killer7 has evolved since the early days of MNF. I'd argue that you can also see that well in the interaction between Lucy, the MC and the whole family dynamic, which has improved greatly: In the beginning Lucy was very passive and tried to hide her features and her mother would never have thought of making cat jokes about her. Makes sense, of course, since Lucy was not yet able to accept herself as she is at that point. Accordingly, you can see a massive development or build-up of self-confidence in both ladies.
How come every time I go into deeper thought processes that I then fabricate an extremely long wall of text?