All acts profile by rixxx with aditional plugins. Its not AFKable, you may have to do some bosses on your own.
Do Normal with self-found gear.At 25 you can buy a little gear or at least Cain's set with ruby in helm for xp. when in A3 & level 30 stop. Skip A4
Buy vit & base stat gear with good dps weapon, possible life on kill and ruby gem. Go to Nightmare
A1 at butcher you will be around 37, a little act 2 so you are 40.
Buy another better gear with good dps weapon.
Do Nightmare Archon Speedrun profile some where on this forum, change in XML difficulty to nightmare. Do this till 50. Its quick
Then another gear buy, buy weapon with around 1k dps and and base stat and vit. I had around 25k HP and 15k dps i think. Do Hell Speedrun till 60.
You can do it in a half-day to day. I started overnight and had some stucks at bosses so it was a waste for me, but next night it was leveled to 60.
i spent around 2-3m for all 3 packs of gear. Don't forget to buy full stash first time you are in town (for the plugin). And set ignore in autoequipper for Cain's slot items. I keep them till i am 60.
To sum the runs:
Normal A1-A2-A3 (1-30 level)
Nightmare A1-A2 (30-40) do A3 Speedrun (40-50)
Hell A3 Speedrun (50-60)