What would you do with a small swarm in spring?

Hi again -

Caught a pretty small swarm today and I'm trying to decide what sized box to put them in. A nuc? Let them go straight into an 8-frame deep? I don't have any drawn comb to provide since I'm new to all this.

When would you make the transfer from the box I caught them in to a new setup? I plan to prophylactically treat for varroa his week.

Any tips and experiences are appreciated!