So.. you're new.. and you want to get your WL up to lvl 170 ASAP! Doesn't everyone want that?
Without further adue.. here's a suggestion to achieve lvl's like you never have before
When creating an account, obviously pick your WL and go through the introduction phase. Once you're able to customize your brig, dismiss or feed all familiars! You're only left with your WL. But why?! I like my Baego and my Piggy!.. The fact is: When you enter in fights with multiple familiars, your experience gets distributed evenly to each one. Playing with your WL only, guarantee's maximum XP gained per fight.
A bonus to new players is given for up to a certain amount of days. First, a 1.5x XP bonus takes into effect and then this switches over to 2x XP gained for skill leveling (not sure exactly how many days for each bonus). With the 1.5x XP multiplier you are guaranteed leveling before running out of energy and morale. Once you hit higher levels, you'll have to spend your energy and morale a little more efficiently to gain the optimal results.
Now to the juicy stuff...
Whatever you do, DO NOT open any silver or copper coin pacts! Whenever a new fam hits your account, this will determine your matchups for PVP. Now that I mentioned PVP, you'll notice you will be hitting a nice win streak, due to the fact you havent touched your account besides lvling your WL. Most opponents you will face are lvl 5-15 with a Baego and a C/UC familiar. Once you're at lvl 20+, this becomes a breeze and you gain roughly 300-400xp per PVP battle. Just recently, DeNa has changed match up results and once you hit your 14th battle, you will face full 5-man EP brigades. Keep this in mind when rationing out your energy and morale; on your 14th battle against that 5-man brig, you will obviously lose.. BUT! you'll gain around 1,200 XP! (roughly). This will level your WL and you've got refreshed energy and morale.
I keep dying! Ok, so you've hit a point to where you can't solo with your WL anymore in story mode. Thats ok! The best time to start a new account is during RAID EVENTS! Your WL gains 5x to its stats and becomes invincible to story mode!
Now what about the WL Skill? Ok, so after some testing I have come to the conclusion that it is OK to lvl your WL's DEFAULT Skill. Do not add a skill to your WL until you are comfortable with where you are at in the game to start competing. Only level your skill using offerings - this does not effect matchups for PVP.
I haven't gone all out to lvl 170 with just my WL, but I have gone to lvl 120 in a couple days before obtaining 5-man brig formations. If you have the dedication, please comment how long it took you and what problems you ran into while achieving this.
Thanks for reading and Good Luck! :D
Credit to Jareif for helping and contributions to the concept ;)