Ow. That's a low end system on multiple fronts.
The PSU is too low for any upgrade apart from the aforementioned 1050Ti. While it would be an upgrade there imo wouldn't be a SIGNIFICANT boost.
Next up is the CPU. Let's assume the 1060 6GB is installed. The 4300 will be the ball and chain. PC's need balance. Not even the strongest GFX card can compensate for a low end CPU. Basically a PC is a house. The CPU can be see as the framers and drywallers, those who erect the skeleton of the house. The GPU can be seen as the painter. They bring the polygons to life in a crude manner of speaking. The painters need to wait for the framers. The 4300 is a slow framer. The 6300 would be better and the 8350 would be better.
The 1060 would be on par with the 8350 but then his PC wouldn't have enough to eat.
https://www.newegg.com/Product/Product.aspx?Item=N82E16817139202 solves the PSU issue.