Welcome!
In terms of buying new gear, this site is no doubt a wealth of info.
In the end, what works for others may not work for you. I would go to a competition and see what kinds of gear people are running. Ask them what they like about it and if you could take a look. At my local range, people love sharing what they have and will even allow you to dry fire their rifle if it's safe to do so (this is the best way to get a feel for some of the custom actions out there). Competitors (at least in my experience) are generally very friendly to newcomers, so feel free to ask away!