Gaming computer Query?

What

Definitely the graphics card. The 750 ti is a lower end and older model. Whoever you bought that from ripped you out of some money - people often put in a decent amount of ram and and an i7 so those of us who are less knowledgeable believe it to be a higher end gaming pc when in reality what matters most is the graphics card. All of your other specs are good enough for all gaming unless you plan on going 4k. I would suggest an nvidia card over an amd card. I would suggest a GTX 970 at the lowest and would suggest the GTX 1070 if you can afford it at ~$450.

"Is there anything in particular I should be looking for without going Too overboard on one particular part with the rest of it being imbalanced"
You may want to upgrade ram by adding another 2x4gb kit or a 1x8gb kit (depending on what came with it, one 8gb stick or 2 4gb sticks, you want to be consistent with ram) but 8gb isn't too bad these days. Definitely some time in the future though.

"Also, is there any software I can use to maximise gaming performance or anything I can do in general to keep things running smoothly? "
I would recommend MSI afterburner and CPU-z, they show you what temperatures your cpu and gpu are running at respectively and what clocks they are running in the system tray at and a bunch of nerd stuff. Afterburner also displays this at the top corner of gaming applications so you know what FPS you are getting and what temperature your card is at under load so you can know if it's overheating.

feel free to ask more questions

Pas mal, je t'apprécie

If you're fine with low settings and/or 30 FPS, you don't really need to upgrade anything for 1080p. But if you want more than that, get this: https://pcpartpicker.com/product/D44NnQ/evga-geforce-gtx-1050-ti-4gb-ssc-gaming-acx-30-video-card-04g-p4-6255-kr
That should be able to handle 1080p medium settings 60 FPS.

The Core i7-4770k is still an excellent gaming CPU. The only reason any of the newer ones are better is because they can attain a higher clock speed. With 4k or anything with a 60fps target range, the 4770k is as good as any other CPU out there.

The only reason to ditch the 4770k is you needed a faster CPU for driving a 144hz monitor. On the other hand, overclocking the 4770k would erase that need to upgrade. The only people who have upgraded from it are enthusiasts who want the best of the best.

8gb of RAM is suitable, unless you upgraded to a GTX 1080ti with a 4k monitor. Then 16gb would be usful.

The GTX 750ti is weak. You could play AAA games at medium to low settings at 1080p.

I would recommend a card like a 6gb GTX 1060 of you want impressive gaming results. You would need to have a 450w or better power supply for this card. You can run cards like the GTX 1070, the upcomi

You can use Windows to set the games to a higher priority while keeping background tasks to a minimum.