Since you said you only played the game "one time through", it seems like you have most of the fun still ahead of you ;-)
I'd strongly recommend playing seasons and starting over, as you'll find lots of people there and the season journey will keep you busy in the beginning - including some nice rewards along the way (you get one free class set relatively early on). I'd actually encourage you to *not* read to much but just enjoy the game and make your own discoveries. Play whatever you want (class-wide, build-wise) for as long as it keeps you entertained. Only advice is that if you want to do bounties, do them on Torment 1 and in a group in the beginning - otherwise you'll waste some time for very little reward there. Once you feel "bored" or "stuck" it's early enough for you to look up guides or pursue higher goals, but usually at this stage the game changes a lot and in my opinion the way to get there is one of the most fun experiences you can have in D3, so you shouldn't spoil it too much.