If Kael is already maxed, go with High Khatun. 

I just got lucky and drew a Seeker. Should i still go with high khatun?

I think Seeker is more useful throughout the game and in later game content. I'd go with Seeker. 

I wouldn't mind seeing the roster just to double check. I don't see Seeker as a champ with as much early game progression value as HK, but wouldn't mind seeing the roster.

I do like that HK is a speed lead with a nice aura.

Honestly, a first team of HK, Seeker, Venus, Kael and Ronda is pretty decent. And a first arena team of HK, Seeker, Venus and first Kael then Ronda to nuke is nice too.

You get lots of TM boost, both from Seeker and HK, Inc Speed from HK, Inc Atk from Seeker, an AoE TM decrease from HK, a speed aura from HK, a nice inc defense passive from Seeker, your aoe dec defense and weaken from Venus, an AoE HP burn from Venus, Poisons and AoE Damage from Kael, and block passives and actives and lovely AoE damage from Ronda.

Honestly that is a sweet starting 5.