As a new player should I be using my event tickets/arcana to try and get Hati, or should I use it at Holy City Tarvern or the original Tavern? I was able to beat Hatifas at fight 10, but just barely and I needed to use all 3 orbs at once to do it.
Fight your way to 50, and get 1 copy of Hatifas. Stages 30, 40 and 50 are hell, but aside from those you should be okay (if you have any Hati friends that should be enough, until 50 at least).
As to where to pull... Usually, it goes like this: Skip Vice Capital and consider the Holy Capital (because Lilith, Parchelle and Wayne). Do not even consider Maze Pass and only pull at Sage's Tower if you really want a mage. Pull at Lake of Sand for buffers that will make raids easier.
However, if we account for Gumi's features (TM) and the fact that you are a new player and possibly missed Coro, Selene and Trystan... Your best bet is to pull at fests for now (VC has warrior units but they are quite outdated, and you probably are far from The 9 Territories and v2 taverns).
I was going to ramble about how this one isn't good for new players, but it features 2 good dancers (although Hassan is outdated), some crafters and, most importantly, Sonya and Hati. Sonya is a solid warriro that WILL last you through v2 as well as v1. They introduced a Sonya-only sword which buffs her a lot in mage-soldier comps just a couple of weeks ago, but until there you should be able to manage with new units+her, just keep that in mind.
HOWEVER if you feel you can make do for now, I'd wait until they announce next week's fest, in case it's better or they decide to launch v2's second tavern (wouldn't count on it, really) - or even better Trelancia! Because Gumi never cared about launch dates at all.