Well, tbh 1080p 144hz it's really good if you can keep the frames up. 144hz feels really good, you maybe won't notice the 144hz right away, but when you go back to 60hz you will miss a lot the extra refresh rate. I had a 60hz and happily upgraded to a 144hz one. In my opinion Rainbow Six, Overwatch and R League benefit a lot from the higher refresh rate. Now if you desire fancier looks and maybe do some productivity then go ultrawide, I personally do not recommend 4K, since I'm a fan of high refresh rates and 4K 144hz requires too much hardware to maintain. Try out the 144hz monitor, if you do not like it just return it to the store, most of the reputable tech stores offer a 30-day return policy.
EDIT: If you are mostly doing content stuff then ultrawide or a higher resolution might be better, ultrawide would be more beneficial for you, regarding productivity. The problem with high refresh rate monitors is that usually, they lack quality color reproduction. If that is important to you stay away from them. +1 to Ultrawide.