Which character’s Zeta ability next? Need some advice.

Greetings,
I am not certain which character "to Zeta" next. I am always looking what characters I have and which abilities are useful in general, but therefore my squads with synergy are not maxed. For example, I have a CLS-lead team where I also use old Ben, but his abilities are not maxed because I don’t see a use to actually give him such rare resources.

So, what shall I do? Which character would be the best choice to improve his abilities?

I would be very thankful if someone could look at my swgoh.gg account and give me some helpful advice.

Thanks.
Kind Regards.