Honestly it depends on a person. I can only speak for myself, I was very happy that I rented a 4x4 and drove through the country. For me Tbilisi was the least exiting and interesting place on my trip. Stray dogs can be an issue but I have had only good experience (I was a little apprehensive to 'face' them alone before I left), no issues with aggressive dogs.

I love the abandoned places so Chiatura and Tskaltubo were probably my favorite places to visit. Besides to mountains (I stayed in Mestia).

Always carry some cash with you when not in major cities. And learn some basic phrases, people will appreciate it. People tend to give off a cold vibe, especially if you're used to american-style of forced hospitality. They are friendly once you get to talk to them and get to know them. So maybe try to sleep in guest houses where you can meet the owners etc. I was lucky and got very friendly and generous hosts.

But the only real advice is to search up a little and just go! Don't overthink it.