Yes, I would certainly prefer row 7 over row 9. Row 7 is in the small (2 row) front cabin and it gives a 'quieter' feel. Having said that, row 9 is not terrible (I would avoid row 8 as people tend to bump into it on their way to the toilets).
Row 6 is usually (partly) blocked because of the bassinet positions. If you are keen to get it, try via the app from about 3 days out. At some stage (not always the same moment in my experience), it suddenly gets released (assuming there is no need for bassinets).