Should I split my Puglia vacation in 2 locations?

I will be visiting Puglia at then end of July (6 nights) with 4 more friends (all guys). We want to rent a car and do day trips, but mostly relaxing, no extreme sight-seeing but we would like to visit Matera and some of the more southern towns and beaches. I heard the traffic is pretty crazy in July so I was wondering if it would be worth splitting the vacation in 2 locations, my idea was 3 days Lecce (or some other southern location that has some night life, recommendations are welcomed) and 3 days Ostuni?