FWIW, looking at your waits, only 2 stand out.

CXPACKET and WRITE_COMPLETION

You can search on those. But without information about IO load or your disk subsystem I won't comment yet on the write_completion.

CXPACKET could mean you have poor performing indexes. It could mean that you have a CPU bottleneck. It could be benign. It depends on your workload.

But based on the percent_total_waits, none of these indicate a problem.