I am using:
(me) Hospitaler
(Tank) Valerie - Many 5 multiclasses
(DPS) Amiri - TWF,4 muticlasses
(Because) Linzi - Brd, Eldritch
(Healer) Harrim - Cleric

Would you take Ekundayo, Jubilost or Ocatavia? If you would explain why I would appreciate it.

Thanks.

Already answered this on other forums. Would be Jubilost, for anyone wondering.

Octavia gives you access to high level arcane spells . Everyone uses her as an arcane trickster so ranks her up in wizard, for 3 lvels, get extra sneak attack from a feat then arcane trickster 10 levels. She will in essense get to level 19 wizard but also 10 levels for sneak attack to increase also, and will apply to her spell damage too!!
She can do a lot of dps with her sneak attacks but getting access to slow and haste earlier (esp as your protagonist is not spell user) is the real benefit as these spells are the biggest force multiplier in the game and really help in tough fights.
TBH I don't use linzi and octavia takes care of all the traps for me, which levels her up quickly too.
The ranged legerdemain also can be very useful in specific situations (disabling traps without going close to trigger or opening chests in poisonous mist without needing to go inside. Shes also a love interest.

I also use Ekun. He is a beast and almost purposely designed to deal with troll trouble. His DPS is vey high as is his range so no wasted time moving into range. He cang ive you another option to counter wizards and archersi n the backline. Other options involve an amiri charge through but sneak range damage to target backline needs 2 flankers or stealth so generally only comes into play with frontline targets so octavua or a protag other theif can't take backline targets quickly unless they hit with 1st shot and or go invis during a fight.
He has a good build before you get him but I love more bow feats such as many shot etc where you get 2 arrows so 50-60 dmg become a regular thing.
Also his wolf levels up with him and is another absolute beast. You can cast armour on it and the fang spell and now on level 9 I've had his AC on valerie levels of 35 (with those spells.) He gets a name later so feels like a real member of the party. It is better to have more bodies to form a frontline when 10 spiders are encircling you!!

Also in trollswarven city quest you get a great longbow dealing acid damage for him. He has good stats for melee but I keep him as an archer but give him a decent 2 hander in case the backline is threatened. His strength is better for adding dmg to his bow. almost forgot he reduces your need for rations in camping so 12 can last for 3 rests instead of 2 (switched to using rations to save time but you can still hunt and it only uses them if you don't get the full 4)

I don't use jubilost except to take to dwarven city, my treasurer advisor and needs grabbing asap. You can level him up with training and still give him a wisdom boost headgear. Main problem I had with himwas running out of bombs. 10 sounds a lot but is used up quickly.

nice necro

Hardly a necro of just over 2 weeks with lots of relevant information given.