I devoted all resources to Finn and Poe as soon as they became available.
As a non whale (light pay to play until the last 7 day subscription) with a 7* Finn... I don't know what to tell you.
He's handy?
He doesn't shine brightly, but as far as first hit damage goes, you know he won't be the first targeted toon and will probably get off a shot. I just hope you don't need a second.
I use him in my starting arena squad from necessity until I have credits/droids/mats to bring geo s in to replace him.
Slow speed means he can always take advantage of offensive buffs his first turn.
Hold the Line is usually only handy during GW, or some odd times when last man standing against a Dooku or 5's and I look forward to all three effects and getting another turn closer to a possible expose/stun.