As someone who've played all of these games, the true ending REQUIRES following a guide to the letter. It's impossible to get it otherwise and you don't want to spend another 50+ hours trying to get it.
To get the girl's CG or "ending" you need to select the right conversation options which will lower the affection of the other girls. You can forget about saving before the marriage choice so you can see all of their CG since you will usually only have one option available; of course, you can always follow a strict guide.
Other than those issues, the game's story is pretty interesting and you'll know if the gameplay is good enough for you within the first few minutes. I recommend cheating.
To get the girl's CG or "ending" you need to select the right conversation options which will lower the affection of the other girls. You can forget about saving before the marriage choice so you can see all of their CG since you will usually only have one option available; of course, you can always follow a strict guide.
Other than those issues, the game's story is pretty interesting and you'll know if the gameplay is good enough for you within the first few minutes. I recommend cheating.