1 -Start by taking missions from Melee trainor on the island and kill the yubos of the mission (not others at start), you will go trough first 5 lvls very very fast. Kill even a few more than requested by the mission, cant do any bad

2 -When going back to town, always train Con/Meta/Balance/Str as priority, they are the one increasing your HP and stamina pool and regen..
After that you can get new Inc Dmg or Acc attack.
3 -Whn you are around lvl 10-20 melee you will have enough HP to start training off magic (acid by default) without too much risks.
My comment on the one toon compared to two was mainly due to the difficulty to trade between two toons.
Tho, you can easily train one in melee and magic and just sell loots for cash and train the other one for craft and Harvest (in order to get needed mats).
After you make a few friends, you can ask them to help you transfer from one toon to the other..
The game could indeed benefit from one chest like GW which is accessible to all toons
