If you're still on the integrated graphics built into the processor, the graphics card upgrade would give you more of a performance boost than anything. A 1050 Ti should draw less than 75 watts under load, so you might even be able to get away with keeping the same PSU. Nvidia recommends systems have at least a 300 watt PSU for that card, so you probably should check what yours is.
I probably wouldn't bother adding more DDR3 RAM, as it would only likely have a minimal effect on performance in today's games, which still generally get along fine on 8GB, so long as you are not multitasking in other applications while playing games. As was already pointed out, the A8-7600 processor might limit performance a bit in some games, but if you ever decide to upgrade to a faster processor, all the current-generation CPUs require DDR4 RAM (and new motherboards). Since RAM is priced rather high right now, you might not want to buy more than you need.