Lake Havasu City is a retirement town . There is not much to see except for golf courses and mobile home dealerships.
They do have the original " London Bridge " which was dismantled in London and rebuilt in the Arizona desert .
If you return to Vegas in the late afternoon vis highway 95 and 163 you should get a very interesting view of the Black Mountains
on the east side of the Colorado River.
You might also try a drive through the Mojave National Preserve justwest of Bulhead City .
Favorite thing: Pretty much about Lake Havasu City takes place around the famous London Bridge.