Yeah some times the devs can be quite new to whatever software they're using to make images and it leads to the quality improving over time like that. Sometimes the difference from start to finish can be funny
What are your favourite games with a female MC?
Personally I liked Succum Brewery a lot, it has some really good art and a good corruption/hypnosis story. I'm waiting for it to get some more significant updates before playing it again.
Detective Girl of the Steam City was another really good...
Renpy because it has some of the best games on it. HTML can be used to make some really good games like DOL but most are awful.
I wish there were more that used engines like Unity or Unreal but most porn game Devs don't have that kind of skill.
Unfortunately a lot of porn games are made by people with no experience in real game design so the correct path to take can be extremely difficult to deliberately follow