First Time Travelling Georgia

Hey everyone, I have booked a trip to Georgia for my wifes birthday! This will be our first time visiting Georgia and I was just looking for advice on my itinerary:

Tbilisi: 3 days Kazbegi: 2 days Kutaisi: 2 days Mestia: 3 days

Is it worth renting a car after Tbilisi? I have heard that driving in Georgia can be quite chaotic!?

Also, we are planning to visit Ushguli and do a few hikes around that region. Is a 4x4 NEEDED for the drive between Mestia and Ushguli? (We are travelling late August for reference). And should we base ourselves in Mestia and just do a day trip to Ushguli or would it be better to stay overnight in Ushguli and then return?

Also if anyone recommends cutting a day down or adding a day somewhere I will happily take your advice onboard!

Any help would be greatly appreciated! 🇬🇪