If you look at overall cpu usage it seems low... But verification is a single thread process. So one of the 8 or 12 logical CPU's will be maxed out. Buying the fastest single thread CPU would be upgrade that would make the most difference.
https://www.cpubenchmark.net/singleThread.html
GPU's are good for parallel processing not really good at single thread performance. That's why they're never used in Bitcoin nodes.