Hi,
what do u think is the best second class?
i can’t decide…Inquisitor, soldier or shaman?
+Shaman.
/10chars
But why Shaman?
No attack Speed, no OA and wind devil needs micromanagment.
Exclusive Aura is not bad (stormcaller) but i think Aura of censure is better,
just feral hunger+wendigo totem/heal seem to be ok.
Inquisitor. 2-handed Purifier gunslinger > dual-wield Purifier Gunslinger. You can cap attack speed, you are going to have tonns of RR (mines + edritch fire + ignafar combustion relic + elemental storm + hand of ultos + Ulzuin’s headguard), a lot of resists/cc/blast shield, a lot of OA and a lot of critical damage from full mythical Ulzuin’s set.
Shaman mastery is for Vindicator Gunslinger build.
EDIT: Ah shi, melee. Ultos elementalist can be pretty damn strong, but a bit squishy and with quite a bit of skills micromanagement (flashbang + mines + wind devil + transmuted BWC sometimes). Commando is still one of the strongest classes in the game, you can go a lot of ways with melee commando. If it’s your first char, I suggest you go commando (soldier mastery, not wearing pants with no underwear).
2h fire melee?Go soldier.
You get a lot of defensive skills like field command, menhir’s will and big boost to OA with oleron’s wrath. You also excellent itemization thanks to infernal brimstone/sharzul world eater for weapons and justicar set for armour. I have a build like this and it works really well, plus it is super fun to play. 
Inquisitor should also work well, but you will be squishier and with less OA/DA most likely.
Soldier has mirror issue - he got attack speed and OA but no sustain. It’s whichever you feel would be easier to solve. I had played 2H FS melee commando pre AoM and honestly I think FH and Wendigo Totem are good enough to justify Shaman over Soldier. Also Shaman does have OA and attack speed if you’re willing to sneak in some Savagery hits.
No idea why would you consider an Inquisitor.