Who should get the tonics?
I use Tarlak pretty well for titans, and situationally for raids (maybe more if he was maxed lol)
Eve is pretty much a titan killer for me too
Zeline seems to be a hugely popular hero for top ranks
Alberich? Annoyingly good.
Help?
Tarlak for titans
Zeline for raid/war attacks and defenses
Alberich for war defenses
Do you need a healer? Alberich
Do you need a dispeller? Zeline
Do you want to kill bugger titans? Tarlak
Their time will come… are you in need of some hero for emblems’ quests?
Not really 
I currently don’t use a green in my defense team, mostly cuz I can’t not use the others lol
I would recommend Tarlak, I use him almost everywhere. Titan, raid, s2 hard mode.
Only in my def teams he is not used, but could.
But Zeline is much better in def. As well Albi.
Hard choice…
Tarlak does fine at 3/70 for titans (since he only really contributes tile damage on blue, otherwise he’s just a buffer)
I still prefer wu most of the time tho. I’ll take the gamble usually (112k top hit)
Zeline is good, but usually end up raiding guin/GM combos so don’t usually bring greens for those raids (3/2 purp blue)
Edit: let’s appreciate that I’m an idiot and I replied to myself lol
Alby first, since he’ll bring back all the others. 
Then Tarlak for titans.
Then Zeline to farm and fight.
Then Evelyn to stack.
That order will match progressing in the whole game the most imho.