Protank is pretty good, let's call it a 7 on the flavor scale. If you bump up to a microcoil on a Kayfun or similar RTA for the tank feature, flavor will at least be a 9. Though rebuilding is cheaper and tastes better, it is not for everyone. I struggled for a long time, and while I had been close to figuring it out on my own, it took a trip to a couple local vape shops and seeing others do it before I had my AHA! moment.
Certainly what works best for you is obviously what is best for you, but being newer to the scene and not having experienced the difference, you need to make a decision based on actually trying it. I recommend calling some stores and seeing if they can help you and making the trek, even if a bit far, to try one out and/or learn to do it yourself. You will not be disappointed.
I used carto tanks for years and was happy. I tried rebuilding maybe two years ago and gave up on it. After a bunch of stores recently popped up in my area, I met people that knew their stuff and went from there. I could not be happier with my Kayfun. Many like to drip as it often offers the best flavor and juices are more easily switched, but I don't like doing the work when my Kayfun's flavor will be close.
My advice - meet someone who knows their stuff and do it. You will not be sorry!