I like Freya, actually, though till she's housebroken and had her obedience training you may occasionally be calling her Hel !
Since you asked for suggestions:
Agatha
Arwen
Bait (will eventually require a second dog named Switch)
Finster
Maxine
to continue the family's Celtic naming conventions, what about:
Dogda
--Rack
(companion to dog Mingus aka Mangy, Gub, Dumba**; cat Elmo aka Elminster, Elmet, Eeeevil One; and cat Hobie aka Hobart, Beanie, Blockhead)