Recommendation for 150 character purchase for this event

Museum and Plato's character's help the event. Villa and knife character's do not.

The Colosseum only pays out 2 plunder every 4 hours, so not worth it for helping with the event.

I'd go with the Casino and Johnny Tightlips for this event. He's voiced and the casino is a cool building.
Springfield Museum and Malloy(?) would be a close second, he's not voiced but he has a nice animated task to walk around town and case houses to rob. The museum is a very nice building too.
Both help plan heists.
Skip the Coliseum, low payout and it's friggin' tiny.

If you're a 4 hour by 4 hour player (like myself) you can get the Colosseum. However, I would skip it.

I'd lean slightly towards Malloy and the Springfield Museum over Johnny Tightlips and the Plato's Casino; only because I have a burning hatred of 12hr collection times. XD

But, that's just me.

Always choose a character ... the gift that keeps on giving :)

Thanks for the feedback everyone! I’m going to get the casino and museum, maybe the casino first just since it is a higher amount to get it out of the way. With KEMs, I’ll already have 100 donuts left and enough soon to get the other.

Gino makes regular appearances at Christmas time (probably because of the building's name). Francesca and the Italian Villa are much rarer.