After analyze audio ... you can use volume leveling - so everything sounds at same volume ... technically this is not bit perfect (your DAC will not receive same bits as in your audio file ... obviously as the volume is adjusted) but this is done in digital domain at studio quality (bit depth is increased to virtually eliminate quantization errors).
Also, audio analyze will detect and mark audio tracks that have HDCD
You can analyze audio when files are imported (configure Auto-Import)
For things you already imported ... you can select all files then Tools->Advanced Tools -> Analyze Audio ... there you can choose how many files MC can analyze at the same time ... depending on size of your library this might take a while
But you can stop the analyze process ... and do it later ... just repeat above and choose to skip files that already been analyzed
