+x to fire skills and the warlock

i presume items like

Hexfire increase the fire spells in the warlocks Chaos tab...

anyone know for certain?

Yes,

Magefist too, obviously. Flickering Flame is close to bis, if not the bis.

ty. also very cheap re-roll of magic shields:

1 Magic Shield (any type) + 1

Spiked Club (any quality) + 2 Skulls (any quality) --> Magic Shield of Spikes

ilvl=30.
Rerolls the mods on a given type of shield, yielding a magic shield with the "of Spikes" suffix (Attacker Takes Damage of 4-6).
A random prefix may occur as well.
Can be used on any type of shield, including Paladin and Necromancer class items, which may spawn with their usual bonus properties.

Yes,

Hexfire is a good budget option for a Fire Lock (alongside Spirit, of course). If you have one skill point to spare, put it into

Levitation Mastery, that will lower the requirements, especially if you have some +skills to get a higher level

Levitation Mastery.

Or use good old Leaf. It's almost free, and it's one-handed for Warlock!

Great idea!