There are already games that need more CPU, either in cores or threads. This will only increase as time goes on.
Since you already have this setup I'd say a videocard upgrade is worth it for MOST games. A 1gb 650 won't cut it at 1080p, it's not really great for 720p either. Look for a 2gb DDR5 card of at least GTX 660 level, or AMD HD 7870 level. A card like that would match up well with your CPU. Newer cards, like a GTX 1050, use less power and so are more desirable considering your power supply. I'd say a 1050 Ti is the most card you should get for that system, considering prices today.
To give you an idea of what I'd suggest depending on the games you play, Overwatch and Fortnite- 1050 GTX or similar is great. PUBG- 1050 Ti. Assassin's Creed Origins, Far Cry 5, Battlefield 1 multiplayer- you need more CPU and videocard to really get good performance.