I've only had a single bachelor sim live there and he moved out when he got married. He wasn't in there long enough to have any issues. I think he had exercise equipment in the "other open bedroom".
It is an attractive bungalow in a convenient location. I've renovated some of the starter homes but not that one. Your renovation does make a lot of sense and add space. Sometimes what looks nice on the outside isn't that functional inside.
I do play with the pre-made houses. They usually have more complex roofing and small architectural details than anything I'd build, but I probably need to do a tutorial on the more complex aspects of building.
As for the kitchen being far from the dining room, I'd probably add a little table near the kitchen. In some cultures, kitchens are smaller and hidden away due to heat, cooking smells and catching on fire. I doubt that was the logic for this one but you'll see that in older houses. Large open plan kitchens are a very modern concept.