Hi @vca007,
Those complex IDs contain useful info for comparison against other studies — before switching IDs, I recommend reading a bit more on what these represent:
But if you really want to swap the IDs, you can use qiime feature-table group to relabel the IDs to be whatever you want. Here is an example of relabeling to use the sequences themselves, but you can create any label you like as a tab-delimited "feature metadata" file with the original feature IDs in the left-hand column and the new id in the right-hand column: