Depends on how complex your games are gonna be, but i will say it does seem to be a pretty good spec machine. It’s not like your gonna create elder scrolls.
A little bit better graphics card would be better. Better to skimp on the other parts if you can. 750ti is a bit of a stretch in my opinion. I’d suggest a minimum 1050 or 1050ti(or used 960) or AMD 460/470. In general i encourage people to go with newest(er) generations of video cards… Long term support, performance fixes, and features are added by generation (architecture) usually. So in the long term 1050 TI > 960 , but thats my opinion 
In general i would recommend nothing less than a RX 470 ~170 EURs] for UE4. (or that overpriced 1060 3Gb that is practically ****, but still costs 33 EURs more [203 EURs])
In terms of CPUs… hard to make any decisions right now, because Intel will have to lower its prices in the next 5-6 weeks, when “Ryzen” launches… so i think it is a waste of money to buy any CPU right now. (i personally would wait that 5 weeks, and then decide to buy something)
Everything else is up to your personal Flavour.