Personally I don't especially try to fit the good number of engines in such a case. Let's take your first stage for example: the number of engine is correct, but they were assembled in a cross pattern. In a 2D game you can't really recreate that, they appear to be in a row.
That's why I tend to prefer that kind of build:
View attachment 11658
View attachment 11659
View attachment 11660
Only 3 engines for the first stage, but this is closer to what a real Saturn V would look like when it's seen from the side.
Moreover, engines are very powerful in this game: even with 3 Titan, my thrust/weight ratio is above 2 (it was only 1.14 for the real one
). I even managed to do the full Moon mission with throttle capped at 60% with this one.
Your recreation is cool though, good work.