agreed. for the GPU, it is best to look into the used market. That is, if there is such a thing where you live.
The CPU is a bottleneck no matter which way you look at it in terms of modern AAA titles, but all in all it's still competent and you could do to upgrade the GPU instead. However, you're looking at it the wrong way around. It's not the GPU bottlenecking the CPU you should be worried about but the CPU bottlenecking the GPU.
99-100% GPU usage with less than 90% CPU usage is what you want. Not 90%+ CPU with low% GPU.