Its not really the domain spells that make the arcana cleric good, its being able to use wizard cantrips and key them off wisdom and they count as cleric spells.
Then at level 8 you get to add your wisdom modifier to cleric damage which in green flames blades case it already does 1d8+5 (20 wisdom), so you add it again. Shillagh staff for another 1d8.
2d8+10
Throw in spiritual guardians for another 3d8 damage. But you're also level 8 you can upcast that to 4d8. Lasts 10 minutes in a dungeon that is probably 2 or 3 fights, can cast 5/long rest at level 8. Probably want warcaster in there but even with the default array at level 1 you can have 16 wis, 14 con, 14 dex, and you wear medium armor. You use GFB for your melee and probably pick up ray or frost or firebolt as your ranged cantrip, maybe sacred flame/toll the dead, guidance.
Variant human, lvl 1 grab arcane initiate for a Druid spell (probably faerie fire), shillagh+ 1 more Druid cantrip. You'll have around 7 cantrips IIRC all keyed off wisdom.
Pick some decent cleric ranged spells and you're good to go.
My wife put most of the build together, I only spotted the synergy between GFB and being level 8 wisdom to cantrip damage. Outside the light cleric its probably one of the best clerics in the game. Other melee beatdown clerics look good but are a bit MAD.