That's an awesome idea! And since I was having concerns about rounding out the Mirkwood culture (it can't JUST be spiders!) your idea will work perfectly.
And here's the Elven cardlist:
Elven Culture (32 Cards):
40. Banner of Rivendell
(Possession, R)41. The Broken Sword
(Event, R)42. Citadel of Ancient Knowledge
(Condition, R)43. Crown of Leaves
(Artifact, R)44. Elrond, The Halfelven
(Ally, U)45. Enchantments
(Condition, C)46. Erestor, Trusted Counsellor
(Ally, R)47. Food and Provisions
(Event, C)48. Galadriel, Daughter of Finfarfin
(Companion, C)49. Galadriel, Oldest of the Noldor
(Companion, R)50. Galion, King's Butler
(Ally, C)51. Greenwood Bow
(Possession, C)52. Greenwood the Great
(Condition, U)53. Greenwood Sword
(Possession, C)54. Lamps in the Branches
(Event, C)55. The Last Homely House
(Event, C)56. Legolas, Descendant of Orophir
(Companion, R)57. Legolas, Sindaran Elf
(Companion, C)58. Lindir, Singer of the House
(Ally, C)59. Out of Gondolin
(Event, R)60. Rivendell Scout
(Companion, C)61. Scout's Spear
(Possession, C)62. A Short Rest
(Event, C)63. Steed of Rivendell
(Possession, C)64. Sure Shot
(Event, C)65. Tauriel, Head of the Guard
(Companion, C)66. Tauriel, Woodland Warrior
(Companion, R)67. Tauriel's Daggers
(Possession, R)68. Thranduil, Woodland King
(Ally, R)69. Unwelcomed
(Event, C)70. Upon Them as We May
(Condition, U)71. White Star Within Her Hand
(Condition, R)Gollum has been getting neglected on my end, so his culture is next!