Coffee tables should be the same height as the surrounding seating with 18 inches being a good average (although it will depend on your furniture). If you select a coffee table with a lip make sure the lip isn’t higher than the adjacent seating or you’ll end up hitting your drink against the lip when you try to set it down. The idea is to put your drink down not up.
Solid tabletops usually have a very square corner. If you have little kids or the circulation is tight allow extra space at the ends so it’s easier to get around the corners without hitting your shins. Go for color with an upholstered coffee table as it will draw people to the surrounding sofas and chairs. Top it with a tray to hold books and other items (and to soften a strong color such as the pink).