Nice interior layou! I agree that the downstairs windows don't appear very modern. You may want to consider making the stairs 1 tile wide - or adjusting the wall. It always makes me nervous that sims will get "stuck" when there is only one tile as a pathway. I might also suggest using the "place friezes on" cheat, the half wall, or an adjusted wall - if you use CFE - to add more height on the roof of at least parts of the house. The windows are awfully close to the roof otherwise. It also "breaks up" some of the lines. I'm not sure about the black roof. Perhaps a dark gray / asphalt color? Good job!
You have a very good start. But is there another door for the garage you could use? The brown one looks oldfashioned. Sorry.
P.S I don´t mind the fences around your pool. But the lot could do with more trees ro something. It´s not nice to be seen by everybody when taking a swim.