What follows is based on my experience as a Human Elementalist in BWE3 and all subsequent Stress Tests. He made level 16 and he was defeated often. I was horrible at combat until around level 14. This same character will be my first character to play in the headstart.
Alone against the world:
The Elementalist has 4 weapon skills to unlock for an equipped weapon and 4 weapon skills to unlock for an underwater weapon for each attunement. These weapon skills are unlocked after a number of kills are made with that weapon. In order to get these kills, the elementalist must inflict the killing blow in the fight. If other players are involved in the fight, the elementalist has a reduced chance to be the one to inflict the killing blow. The elementalist must set out on his own to get these kills to get these weapon skills unlocked efficiently.
1) Go somewhere away from other players to be alone with the prey. If the elementalist is too near other players when picking a fight with something, the other players are likely to come "help" and prevent you from getting the kill.
2) Pick prey that you can kill by yourself. Things that move slowly or don't move at all are an excellent choice.
3) Engage only one at a time. Avoid things that are in groups. A low level elementalist with poor combat skill fighting 6 Centaurs is not a pretty sight.
4) Check the area around you. You don't want any champions or veterans or big deadly things sneaking up on you. For example: Killing defenseless salmon underwater might be great for this, but not if a 15 foot shark is circling behind you.
5) Pick prey that will give you what you need. Bagging 24 hooves is not a good haul. Earth elementals frequently drop gem stones. Everything on the Hero panel has an upgrade slot except for your gathering tools. I used 15 gem stones filling those slots, including the breathing mask and the underwater weapon. That added 15 points of Power, 15 points of Toughness, and 15 points of Health.
6) Don't get upset when you are defeated. It will happen. You are alone. No one is going to revive you. You have to spend coppers to get to the nearest way point and to get your armor repaired.
7) Take a break. Do a renown heart, a skill challenge, a dynamic event, unlock a way point, some points of interest and vistas, gather some copper ore and wood. Advance your personal story.
Crafting:
I wanted to make my own armor and not to buy any crafting materials from other players. I chose Tailoring as a profession because a tailor can make the light armor I need. 4 of my 5 characters at launch will wear light armor. My elementalist will supply armor to these characters. The main ingredient
needed for low level light armor is Jute Scraps. When I got a new piece of armor and equipped it, I salvaged any armor that I no longer needed to get Jute Scraps. I hunted bandits. They frequently dropped Jute Scraps or stuff that I could salvage to get Jute Scraps. I did not craft the 8 Slot Jute Bags,
but saved my Jute for armor crafting. I chose Armorsmithing as a profession because an armorsmith can make the insignia that the tailor needs and runes for upgrade slots. I crafted 8 Slot Reinforced Bronze Boxes which are made of mainly copper and copper ore is easier to come by than Jute Scraps.
I hope some of you that are considering the Elementalist as a character choice will find this helpful.