As far as I know, Nutro is a medium to good quality dry food but vastly too expensive (in Germany). You may want to try Felidae dry food, which is better quality than Nutro and (in Germany) not as expensive.
As for the canned food, it may be a good idea to make sure that it has no sugar or caramel added ... apart from that, go for the highest amount of meat you can afford in your budget. In Germany, Whiskas and most of the others brand names actually have about 4 % of meat contained in their cans.
Anyway, you could try and offer your cat 20 % of his feed in raw meat - this is usually not more expensive than Whiskas and does a whole lot of good.